docs(browser): fix layer rules — renderer/dom is integration, not platform

Co-authored-by: Daniel Imms <Tyriar@users.noreply.github.com>

AGENTS.md

@@ -98,3 +98,15 @@ const cell = line?.getCell(0);
 ## Writing unit tests
 
 - Unit tests live alongside the source code file of the thing it's testing with a .test.ts suffix.
+
+## Cursor Cloud specific instructions
+
+**Demo server**: Start with `npm start` (port 3000). The demo server uses node-pty to spawn real shell sessions over WebSocket. Integration tests auto-start it via Playwright's `webServer` config, so you don't need to start it manually for `npm run test-integration`.
+
+**Build before testing**: Always run `npm run build && npm run esbuild` before `npm run test-unit`. Integration tests also need `npm run esbuild-demo-client` and `npm run esbuild-demo-server`. The update script handles this automatically on session start.
+
+**No external services**: This project has zero external dependencies (no databases, Docker, or APIs). Everything runs locally with Node.js.
+
+**TypeScript compiler**: The project uses `tsgo` (native TypeScript compiler preview) rather than standard `tsc`. It's installed via the `@typescript/native-preview` package.
+
+**Lint only changed files**: Prefer `npm run lint-changes` over `npm run lint` when iterating on code changes — it's significantly faster.

addons/addon-image/README.md

@@ -1,6 +1,7 @@
 ## @xterm/addon-image
 
-Inline image output in xterm.js. Supports SIXEL and iTerm's inline image protocol (IIP).
+Inline image output in xterm.js. Supports SIXEL, iTerm's inline image protocol (IIP)
+and partially Kitty's terminal graphics prtocol (TGP).
 
 
 ![](fixture/example.png)
@@ -43,9 +44,6 @@ terminal.loadAddon(imageAddon);
 
 ### General Notes
 
-- *IMPORTANT:* The worker approach as done in previous releases got removed.
-  The addon contructor no longer expects a worker path as first argument.
-
 - By default the addon will activate these `windowOptions` reports on the terminal:
   - getWinSizePixels (CSI 14 t)
   - getCellSizePixels (CSI 16 t)
@@ -73,7 +71,7 @@ terminal.loadAddon(imageAddon);
 
 - **Cursor Positioning**  
   If scrolling is set, the cursor will be placed at the first image column of the last image row (VT340 mode).
-  Other cursor positioning modes as used by xterm or mintty are not supported.
+  Other cursor positioning modes as used by xterm or mintty are not supported for sixel.
 
 - **SIXEL Palette Handling**  
   By default the addon limits the palette size to 256 registers (as demanded by the DEC specification).
@@ -100,17 +98,24 @@ terminal.loadAddon(imageAddon);
   Set by default, change it with `{iipSupport: true}`.
 
   The IIP implementation has the following features / restrictions (sequence will silently fail for unmet conditions):
-  - Supported formats: PNG, JPEG and GIF
+  - Supported formats: PNG, JPEG, GIF and QOI
   - No animation support.
   - Image type hinting is not supported (always deducted from data header).
   - File download is not supported.
   - Filename gets parsed but not used.
   - Strict base64 handling as of RFC4648 §4 (standard alphabet, optional padding, no separator bytes allowed).
-  - Payload size may not exceed CEIL(sizeParameter * 4 / 3).
   - Image scaling beyond terminal viewport size is allowed (e.g. `width=200%`).
   - Image pixel size is restricted by `pixelLimit` (pre- and post resizing).
-  - Size parameter is restricted by `iipSizeLimit`.
+  - Playload size is restricted by `iipSizeLimit`.
-  - Cursor positioning behaves the same as for sixel (see above).
+  - size parameter is not mandatory anymore.
+  - Cursor gets positioned at the next cell of the last image line.
+  - ReportCellSize sequence is supported.
+  - Hi-res display support is currently limited (image gets blurred).
+
+- **Kitty Graphics Support (TGP)**  
+  Set by default, change it with `{kittySupport: true}`.
+
+  Note that the kitty graphics support is still WIP.
 
 
 ### Storage and Drawing Settings
@@ -127,6 +132,7 @@ The addon exposes two properties to interact with the storage limits at runtime:
 By default the addon will show a placeholder pattern for evicted images that are still part
 of the terminal (e.g. in the scrollback). The pattern can be deactivated by toggling `showPlaceholder`.
 
+
 ### Image Data Retrieval
 
 The addon provides the following API endpoints to retrieve raw image data as canvas:
@@ -140,6 +146,7 @@ The addon provides the following API endpoints to retrieve raw image data as can
   The buffer position is the 0-based absolute index (including scrollback at top).
   Note that the canvas gets created and data copied over for every call, thus it is not suitable for performance critical actions.
 
+
 ### Memory Usage
 
 The addon does most image processing in Javascript and therefore can occupy a rather big amount of memory. To get an idea where the memory gets eaten, lets look at the data flow and processing steps:
@@ -180,8 +187,8 @@ _How can I adjust the memory usage?_
   A constructor setting, thus you would have to anticipate, whether (multiple) terminals in your page gonna do lots of concurrent decoding. Since this is normally not the case and the memory usage is only temporarily peaking, a rather high value should work even with multiple terminals in one page.
 - `storageLimit`  
   A constructor and a runtime setting. In conjunction with `storageUsage` you can do runtime checks and adjust the limit to your needs. If you have to lower the limit below the current usage, images will be removed in FIFO order and may turn into a placeholder in the terminal's scrollback (if `showPlaceholder` is set). When adjusting keep in mind to leave enough room for memory peaking for decoding.
-- `sixelSizeLimit`  
+- `sixelSizeLimit | iipSizeLimit | kittySizeLimit`  
-  A constructor setting. This has only a small impact on peaking memory during decoding. It is meant to avoid processing of overly big or broken SIXEL sequences at an earlier phase, thus may stop the decoder from entering its memory intensive task for potentially invalid data.
+  Constructor settings. This has only a small impact on peaking memory during decoding. It is meant to avoid processing of overly big or broken image sequences at an earlier phase, thus may stop the invoked decoders from entering memory intensive tasks for potentially invalid data.
 
 
 ### Terminal Interaction
@@ -211,23 +218,5 @@ _How can I adjust the memory usage?_
 
 ### Status
 
-- Sixel support and image handling in xterm.js is considered beta quality.
+- Sixel and IIP support and image handling in xterm.js is considered beta quality.
-- IIP support is in alpha stage. Please file a bug for any awkwardities.
+- Kitty support is in alpha stage. Please file a bug for any awkwardities or missing features.
-
-
-### Changelog
-
-- 0.5.0 integrate with xtermjs base repo (at v0.4.3)
-- 0.4.3 defer canvas creation
-- 0.4.2 fix image canvas resize
-- 0.4.1 compat release for xterm.js 5.2.0
-- 0.4.0 IIP support
-- 0.3.1 compat release for xterm.js 5.1.0
-- 0.3.0 important change: worker removed from addon
-- 0.2.0 compat release for xterm.js 5.0.0
-- 0.1.3 bugfix: avoid striping
-- 0.1.2 bugfix: reset clear flag
-- 0.1.1 bugfixes:
-  - clear sticky image tiles on render
-  - create folder from bootstrap.sh
-  - fix peer dependency in package.json

addons/addon-image/src/IIPHandler.ts

@@ -8,7 +8,7 @@ import { IIPImageStorage } from './IIPImageStorage';
 import { CELL_SIZE_DEFAULT } from './ImageStorage';
 import Base64Decoder from 'xterm-wasm-parts/lib/base64/Base64Decoder.wasm';
 import QoiDecoder from 'xterm-wasm-parts/lib/qoi/QoiDecoder.wasm';
-import { HeaderParser, IHeaderFields, HeaderState } from './IIPHeaderParser';
+import { HeaderParser, IHeaderFields, HeaderState, SequenceType } from './IIPHeaderParser';
 import { imageType, UNSUPPORTED_TYPE } from './IIPMetrics';
 
 // Local const enum mirror - esbuild can't inline const enums from external packages
@@ -23,6 +23,7 @@ const enum DecoderConst {
 
 // default IIP header values
 const DEFAULT_HEADER: IHeaderFields = {
+  type: SequenceType.INVALID,
   name: 'Unnamed file',
   size: 0,
   width: 'auto',
@@ -39,6 +40,8 @@ export class IIPHandler implements IOscHandler, IResetHandler {
   private _dec: Base64Decoder;
   private _qoiDec: QoiDecoder;
   private _metrics = UNSUPPORTED_TYPE;
+  private _isMultipart = false;
+  private _abortMulti = false;
 
   constructor(
     private readonly _opts: IImageAddonOptions,
@@ -52,11 +55,14 @@ export class IIPHandler implements IOscHandler, IResetHandler {
     this._qoiDec = new QoiDecoder(DecoderConst.KEEP_DATA);
   }
 
-  public reset(): void {}
+  public reset(): void {
+    this._hp.reset();
+    this._dec.release();
+    this._qoiDec.release();
+  }
 
   public start(): void {
     this._aborted = false;
-    this._header = DEFAULT_HEADER;
     this._metrics  = UNSUPPORTED_TYPE;
     this._hp.reset();
   }
@@ -76,15 +82,27 @@ export class IIPHandler implements IOscHandler, IResetHandler {
         return;
       }
       if (dataPos > 0) {
-        this._header = Object.assign({}, DEFAULT_HEADER, this._hp.fields);
+        const seqType = this._hp.fields.type;
-        if (!this._header.inline || !this._header.size || this._header.size > this._opts.iipSizeLimit) {
+        if (seqType === SequenceType.FILE) {
+          if (this._isMultipart) {
+            this._isMultipart = false;
+            this._abortMulti = false;
+            this._dec.release();
+          }
+          this._header = Object.assign({}, DEFAULT_HEADER, this._hp.fields);
+          if (!this._header.inline) {
+            this._aborted = true;
+            return;
+          }
+          this._dec.init();
+        } else if (this._abortMulti) {
           this._aborted = true;
           return;
         }
-        this._dec.init();
         if ((this._dec.put(data.subarray(dataPos, end)) as number) !== DecoderConst.OK) {
           this._dec.release();
           this._aborted = true;
+          if (this._isMultipart) this._abortMulti = true;
         }
       }
     }
@@ -93,22 +111,58 @@ export class IIPHandler implements IOscHandler, IResetHandler {
   public end(success: boolean): boolean | Promise<boolean> {
     if (this._aborted) return true;
 
+    if (this._hp.state !== HeaderState.END) {
+      if (this._hp.end()) return true;
+    }
+    const seqType = this._hp.fields.type;
+
+    if (seqType === SequenceType.FILEPART) return true;
+
+    if (seqType === SequenceType.REPORTCELLSIZE) {
+      // OSC 1337 ; ReportCellSize=[height];[width];[scale] ST
+      let width = CELL_SIZE_DEFAULT.width;
+      let height = CELL_SIZE_DEFAULT.height;
+      if (this._renderer.dimensions) {
+        width = this._renderer.dimensions.css.canvas.width / this._coreTerminal.cols;
+        height = this._renderer.dimensions.css.canvas.height / this._coreTerminal.rows;
+      }
+      const scale = this._coreTerminal._core._coreBrowserService?.dpr ?? 1;
+      const report = `\x1b]1337;ReportCellSize=${height.toFixed(3)};${width.toFixed(3)};${scale.toFixed(3)}\x1b\\`;
+      this._coreTerminal.input(report, false);
+      return true;
+    }
+
+    if (seqType === SequenceType.MULTIPARTFILE) {
+      this._header = Object.assign({}, DEFAULT_HEADER, this._hp.fields);
+      this._isMultipart = true;
+      this._abortMulti = false;
+      this._dec.release();
+      this._dec.init();
+      return true;
+    }
+
+    if (seqType === SequenceType.FILEEND) {
+      if (!this._isMultipart) return true;
+      this._isMultipart = false;
+      if (this._abortMulti || this._header.type !== SequenceType.MULTIPARTFILE) return true;
+    }
+
+    // fallthrough for SequenceType.FILE & SequenceType.FILEEND
+
     let w = 0;
     let h = 0;
 
     // early exit condition chain
-    let cond: number | boolean = true;
+    let cond: number | boolean;
     if (cond = success) {
       if (cond = !this._dec.end()) {
-        if (cond = this._dec.data8.length === this._header.size) {
+        this._metrics = imageType(this._dec.data8);
-          this._metrics = imageType(this._dec.data8);
+        if (cond = this._metrics.mime !== 'unsupported') {
-          if (cond = this._metrics.mime !== 'unsupported') {
+          w = this._metrics.width;
-            w = this._metrics.width;
+          h = this._metrics.height;
-            h = this._metrics.height;
+          if (cond = w && h && w * h < this._opts.pixelLimit) {
-            if (cond = w && h && w * h < this._opts.pixelLimit) {
+            [w, h] = this._resize(w, h).map(Math.floor);
-              [w, h] = this._resize(w, h).map(Math.floor);
+            cond = w && h && w * h < this._opts.pixelLimit;
-              cond = w && h && w * h < this._opts.pixelLimit;
-            }
           }
         }
       }

addons/addon-image/src/IIPHeaderParser.test.ts

@@ -4,19 +4,20 @@
  */
 
 import { assert } from 'chai';
-import { HeaderParser, HeaderState, IHeaderFields } from './IIPHeaderParser';
+import { HeaderParser, HeaderState, IHeaderFields, SequenceType } from './IIPHeaderParser';
 
 
 const CASES: [string, IHeaderFields][] = [
-  ['File=size=123456;name=dGVzdA==:', {name: 'test', size: 123456}],
+  ['File=size=123456;name=dGVzdA==:', {type: SequenceType.FILE, name: 'test', size: 123456}],
-  ['File=size=123456;name=dGVzdA:', {name: 'test', size: 123456}],
+  ['File=size=123456;name=dGVzdA:', {type: SequenceType.FILE, name: 'test', size: 123456}],
   // utf-8 encoding in name
-  ['File=size=123456;name=w7xtbMOkdXTDnw==:', {name: 'ümläutß', size: 123456}],
+  ['File=size=123456;name=w7xtbMOkdXTDnw==:', {type: SequenceType.FILE, name: 'ümläutß', size: 123456}],
-  ['File=size=123456;name=w7xtbMOkdXTDnw:', {name: 'ümläutß', size: 123456}],
+  ['File=size=123456;name=w7xtbMOkdXTDnw:', {type: SequenceType.FILE, name: 'ümläutß', size: 123456}],
   // full header spec
   [
     'File=inline=1;width=10px;height=20%;preserveAspectRatio=1;size=123456;name=w7xtbMOkdXTDnw:',
     {
+      type: SequenceType.FILE,
       inline: 1,
       width: '10px',
       height: '20%',
@@ -28,6 +29,7 @@ const CASES: [string, IHeaderFields][] = [
   [
     'File=inline=1;width=auto;height=20;preserveAspectRatio=1;size=123456;name=w7xtbMOkdXTDnw:',
     {
+      type: SequenceType.FILE,
       inline: 1,
       width: 'auto',
       height: '20',
@@ -101,7 +103,7 @@ describe('IIPHeaderParser', () => {
     let res = hp.parse(inp, 0, inp.length);
     assert.strictEqual(res, inp.length);
     assert.strictEqual(hp.state, HeaderState.END);
-    assert.deepEqual(hp.fields, {name: 'test', size: 0});
+    assert.deepEqual(hp.fields, {type: SequenceType.FILE, name: 'test', size: 0});
     hp.reset();
     inp = fromBs(CASES[0][0]);
     res = hp.parse(inp, 0, inp.length);
@@ -115,7 +117,7 @@ describe('IIPHeaderParser', () => {
     let res = hp.parse(inp, 0, inp.length);
     assert.strictEqual(res, inp.length);
     assert.strictEqual(hp.state, HeaderState.END);
-    assert.deepEqual(hp.fields, {name: '', size: 123456});
+    assert.deepEqual(hp.fields, {type: SequenceType.FILE, name: '', size: 123456});
     hp.reset();
     inp = fromBs(CASES[0][0]);
     res = hp.parse(inp, 0, inp.length);
@@ -135,4 +137,124 @@ describe('IIPHeaderParser', () => {
     assert.strictEqual(hp.state, HeaderState.END);
     assert.deepEqual(hp.fields, CASES[0][1]);
   });
+  it('FilePart sequence', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('FilePart=w7xtbMOkdXTDnw');
+    const res = hp.parse(inp, 0, inp.length);
+    assert.strictEqual(res, 9);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(hp.fields.type, SequenceType.FILEPART);
+  });
+  it('FilePart sequence - bytewise', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('FilePart=w7xtbMOkdXTDnw');
+    let res = -2;
+    let pos = 0;
+    while (res === -2 && pos < inp.length) {
+      res = hp.parse(new Uint32Array([inp[pos++]]), 0, 1);
+    }
+    assert.strictEqual(res, 1);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(hp.fields.type, SequenceType.FILEPART);
+  });
+  it('MultipartFile sequence', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('MultipartFile=inline=1;width=10px;height=20%;preserveAspectRatio=1;size=123456;name=w7xtbMOkdXTDnw');
+    let res = hp.parse(inp, 0, inp.length);
+    assert.strictEqual(res, -2);
+    assert.strictEqual(hp.state, HeaderState.VALUE);
+    res = hp.end();
+    assert.strictEqual(res, 0);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(
+      hp.fields,
+      {
+        type: SequenceType.MULTIPARTFILE,
+        inline: 1,
+        width: '10px',
+        height: '20%',
+        preserveAspectRatio: 1,
+        size: 123456,
+        name: 'ümläutß'
+      }
+    );
+  });
+  it('MultipartFile sequence - bytewise', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('MultipartFile=inline=1;width=10px;height=20%;preserveAspectRatio=1;size=123456;name=w7xtbMOkdXTDnw');
+    let res = -2;
+    let pos = 0;
+    while (res === -2 && pos < inp.length) {
+      res = hp.parse(new Uint32Array([inp[pos++]]), 0, 1);
+    }
+    assert.strictEqual(res, -2);
+    assert.strictEqual(hp.state, HeaderState.VALUE);
+    res = hp.end();
+    assert.strictEqual(res, 0);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(
+      hp.fields,
+      {
+        type: SequenceType.MULTIPARTFILE,
+        inline: 1,
+        width: '10px',
+        height: '20%',
+        preserveAspectRatio: 1,
+        size: 123456,
+        name: 'ümläutß'
+      }
+    );
+  });
+  it('FileEnd sequence', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('FileEnd');
+    let res = hp.parse(inp, 0, inp.length);
+    assert.strictEqual(res, -2);
+    assert.strictEqual(hp.state, HeaderState.START);
+    res = hp.end();
+    assert.strictEqual(res, 0);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(hp.fields.type, SequenceType.FILEEND);
+  });
+  it('FileEnd sequence - bytewise', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('FileEnd');
+    let res = -2;
+    let pos = 0;
+    while (res === -2 && pos < inp.length) {
+      res = hp.parse(new Uint32Array([inp[pos++]]), 0, 1);
+    }
+    assert.strictEqual(res, -2);
+    assert.strictEqual(hp.state, HeaderState.START);
+    res = hp.end();
+    assert.strictEqual(res, 0);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(hp.fields.type, SequenceType.FILEEND);
+  });
+  it('ReportCellSize sequence', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('ReportCellSize');
+    let res = hp.parse(inp, 0, inp.length);
+    assert.strictEqual(res, -2);
+    assert.strictEqual(hp.state, HeaderState.START);
+    res = hp.end();
+    assert.strictEqual(res, 0);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(hp.fields, { type: SequenceType.REPORTCELLSIZE });
+  });
+  it('ReportCellSize sequence - bytewise', () => {
+    const hp = new HeaderParser();
+    const inp = fromBs('ReportCellSize');
+    let res = -2;
+    let pos = 0;
+    while (res === -2 && pos < inp.length) {
+      res = hp.parse(new Uint32Array([inp[pos++]]), 0, 1);
+    }
+    assert.strictEqual(res, -2);
+    assert.strictEqual(hp.state, HeaderState.START);
+    res = hp.end();
+    assert.strictEqual(res, 0);
+    assert.strictEqual(hp.state, HeaderState.END);
+    assert.deepEqual(hp.fields, { type: SequenceType.REPORTCELLSIZE });
+  });
 });

addons/addon-image/src/IIPHeaderParser.ts

@@ -6,9 +6,27 @@
 // eslint-disable-next-line
 declare const Buffer: any;
 
+export const enum HeaderState {
+  START = 0,
+  ABORT = 1,
+  KEY = 2,
+  VALUE = 3,
+  END = 4
+}
+
+export const enum SequenceType {
+  INVALID = 0,
+  FILE = 1,
+  MULTIPARTFILE = 2,
+  FILEPART = 3,
+  FILEEND = 4,
+  REPORTCELLSIZE = 5
+}
 
 export interface IHeaderFields {
   [key: string]: number | string | Uint32Array | null | undefined;
+  // sequence type
+  type: SequenceType;
   // base-64 encoded filename. Defaults to "Unnamed file".
   name: string;
   // File size in bytes. The file transfer will be canceled if this size is exceeded.
@@ -29,14 +47,6 @@ export interface IHeaderFields {
   inline?: number;
 }
 
-export const enum HeaderState {
-  START = 0,
-  ABORT = 1,
-  KEY = 2,
-  VALUE = 3,
-  END = 4
-}
-
 // field value decoders
 
 // ASCII bytes to string
@@ -92,7 +102,19 @@ const DECODERS: {[key: string]: (v: Uint32Array) => number | string} = {
 };
 
 
+// sequence type markers
+// File
 const FILE_MARKER = [70, 105, 108, 101];
+// MultipartFile
+const MULTIPARTFILE_MARKER = [77, 117, 108, 116, 105, 112, 97, 114, 116, 70, 105, 108, 101];
+// FilePart
+const FILEPART_MARKER = [70, 105, 108, 101, 80, 97, 114, 116];
+// FileEnd
+const FILEEND_MARKER = [70, 105, 108, 101, 69, 110, 100];
+// ReportCellSize
+const REPORTCELLSIZE_MARKER = [82, 101, 112, 111, 114, 116, 67, 101, 108, 108, 83, 105, 122, 101];
+
+// max allowed chars for sequence header
 const MAX_FIELDCHARS = 1024;
 
 
@@ -111,12 +133,43 @@ export class HeaderParser {
     this._key = '';
   }
 
+  public end(): number {
+    if (this.state === HeaderState.START) {
+      if (this._position === FILEEND_MARKER.length) {
+        for (let k = 0; k < FILEEND_MARKER.length; ++k) {
+          if (this._buffer[k] !== FILEEND_MARKER[k]) return this._a();
+        }
+        this.fields['type'] = SequenceType.FILEEND;
+        this.state = HeaderState.END;
+        return 0;
+      }
+      if (this._position === REPORTCELLSIZE_MARKER.length) {
+        for (let k = 0; k < REPORTCELLSIZE_MARKER.length; ++k) {
+          if (this._buffer[k] !== REPORTCELLSIZE_MARKER[k]) return this._a();
+        }
+        this.fields['type'] = SequenceType.REPORTCELLSIZE;
+        this.state = HeaderState.END;
+        return 0;
+      }
+      return this._a();
+    }
+    if (this.state === HeaderState.END) return 0;
+    if (this.state === HeaderState.VALUE
+      && this.fields.type === SequenceType.MULTIPARTFILE
+    ) {
+      if (!this._storeValue(this._position)) return this._a();
+      this.state = HeaderState.END;
+      return 0;
+    }
+    return this._a();
+  }
+
   public parse(data: Uint32Array, start: number, end: number): number {
     let state = this.state;
     let pos = this._position;
     const buffer = this._buffer;
     if (state === HeaderState.ABORT || state === HeaderState.END) return -1;
-    if (state === HeaderState.START && pos > 6) return -1;
+    if (state === HeaderState.START && pos > 14) return -1;
     for (let i = start; i < end; ++i) {
       const c = data[i];
       switch (c) {
@@ -127,8 +180,29 @@ export class HeaderParser {
           break;
         case 61: // =
           if (state === HeaderState.START) {
-            for (let k = 0; k < FILE_MARKER.length; ++k) {
+            if (buffer[0] === 70) {
-              if (buffer[k] !== FILE_MARKER[k]) return this._a();
+              // 'File' or 'FilePart'
+              let k = 0;
+              for (; k < FILE_MARKER.length; ++k) {
+                if (buffer[k] !== FILE_MARKER[k]) return this._a();
+              }
+              this.fields['type'] = SequenceType.FILE;
+              if (pos === FILEPART_MARKER.length) {
+                for (; k < FILEPART_MARKER.length; ++k) {
+                  if (buffer[k] !== FILEPART_MARKER[k]) return this._a();
+                }
+                this.fields['type'] = SequenceType.FILEPART;
+                this.state = HeaderState.END;
+                return i + 1;
+              }
+            } else if (buffer[0] === 77) {
+              // 'MultipartFile'
+              for (let k = 0; k < MULTIPARTFILE_MARKER.length; ++k) {
+                if (buffer[k] !== MULTIPARTFILE_MARKER[k]) return this._a();
+              }
+              this.fields['type'] = SequenceType.MULTIPARTFILE;
+            } else {
+              return this._a();
             }
             state = HeaderState.KEY;
             pos = 0;
@@ -158,6 +232,7 @@ export class HeaderParser {
   }
 
   private _a(): number {
+    this.fields.type = SequenceType.INVALID;
     this.state = HeaderState.ABORT;
     return -1;
   }

addons/addon-image/src/IIPImageStorage.ts

@@ -3,6 +3,7 @@
  * @license MIT
  */
 
+import { IAddImageOpts } from 'Types';
 import { ImageStorage } from './ImageStorage';
 
 /**
@@ -12,6 +13,7 @@ import { ImageStorage } from './ImageStorage';
  * - Always uses scrolling mode (cursor advances with image)
  */
 export class IIPImageStorage {
+  private _addImageOpts: IAddImageOpts = { scrolling: true, layer: 'top', zIndex: 0, cursorPos: 'iip' };
   constructor(
     private readonly _storage: ImageStorage
   ) {}
@@ -21,6 +23,6 @@ export class IIPImageStorage {
    * Always uses scrolling mode — cursor advances past the image.
    */
   public addImage(img: HTMLCanvasElement | ImageBitmap): void {
-    this._storage.addImage(img, true);
+    this._storage.addImage(img, this._addImageOpts);
   }
 }

addons/addon-image/src/IIPMetrics.test.ts

@@ -30,7 +30,8 @@ const TEST_IMAGES: [string, IMetrics][] = [
   ['iphone_hdr_YES.jpg', { mime: 'image/jpeg', width: 3264, height: 2448 }],
   ['nikon-e950.jpg', { mime: 'image/jpeg', width: 800, height: 600 }],
   ['agfa-makernotes.jpg', { mime: 'image/jpeg', width: 8, height: 8 }],
-  ['sony-alpha-6000.jpg', { mime: 'image/jpeg', width: 6000, height: 4000 }]
+  ['sony-alpha-6000.jpg', { mime: 'image/jpeg', width: 6000, height: 4000 }],
+  ['dice.qoi', { mime: 'image/qoi', width: 800, height: 600 }],
 ];
 
 

addons/addon-image/src/ImageAddon.ts

@@ -137,11 +137,6 @@ export class ImageAddon implements ITerminalAddon, IImageApi {
 
     // enable size reports
     if (this._opts.enableSizeReports) {
-      // const windowOptions = terminal.getOption('windowOptions');
-      // windowOptions.getWinSizePixels = true;
-      // windowOptions.getCellSizePixels = true;
-      // windowOptions.getWinSizeChars = true;
-      // terminal.setOption('windowOptions', windowOptions);
       const windowOps = terminal.options.windowOptions ?? {};
       windowOps.getWinSizePixels = true;
       windowOps.getCellSizePixels = true;
@@ -260,7 +255,7 @@ export class ImageAddon implements ITerminalAddon, IImageApi {
   }
 
   private _report(s: string): void {
-    this._terminal?._core.coreService.triggerDataEvent(s);
+    this._terminal?._core.input(s, false);
   }
 
   private _decset(params: (number | number[])[]): boolean {

addons/addon-image/src/ImageRenderer.ts

@@ -146,7 +146,7 @@ export class ImageRenderer extends Disposable implements IDisposable {
   public clearLines(start: number, end: number, layer?: ImageLayer): void {
     const y = start * (this.dimensions?.css.cell.height || 0);
     const w = this.dimensions?.css.canvas.width || 0;
-    const h = (++end - start) * (this.dimensions?.css.cell.height || 0);
+    const h = (end + 1 - start) * (this.dimensions?.css.cell.height || 0);
     if (!layer || layer === 'top') {
       this._layers.get('top')?.clearRect(0, y, w, h);
     }

addons/addon-image/src/ImageStorage.ts

@@ -5,7 +5,11 @@
 
 import { IDisposable } from '@xterm/xterm';
 import { ImageRenderer } from './ImageRenderer';
-import { ITerminalExt, IExtendedAttrsImage, IImageAddonOptions, IImageSpec, IBufferLineExt, BgFlags, Cell, Content, ICellSize, ExtFlags, Attributes, UnderlineStyle, ImageLayer } from './Types';
+import {
+  ITerminalExt, IExtendedAttrsImage, IImageAddonOptions, IImageSpec,
+  IBufferLineExt, BgFlags, Cell, Content, ICellSize, ExtFlags, Attributes,
+  UnderlineStyle, IAddImageOpts
+} from './Types';
 
 
 // fallback default cell size
@@ -235,13 +239,15 @@ export class ImageStorage implements IDisposable {
   /**
    * Method to add an image to the storage.
    * @param img - The image to add (canvas or bitmap).
-   * @param scrolling - When true, cursor advances with the image (lineFeed per row).
+   * @param opts - Options for addImage:
-   *   When false, image is placed at (0,0) and cursor is restored (DECSET 80 / sixel origin mode).
+   *   - scrolling:  When true, cursor advances with the image.
-   * @param layer - Which canvas layer to render on ('top' or 'bottom').
+   *                 When false, image is placed at ORIGIN and cursor does not move.
-   * @param zIndex - Z-index for image layering within the same layer.
+   *   - layer:      Which canvas layer to render on ('top' or 'bottom').
+   *   - zIndex:     Z-index for image layering within the same layer.
+   *   - cursorPos:  'vt340' for bottom-left, 'iip' for bottom.right.
    * @returns The internal image ID assigned to the stored image.
    */
-  public addImage(img: HTMLCanvasElement | ImageBitmap, scrolling: boolean, layer: ImageLayer = 'top', zIndex: number = 0): number {
+  public addImage(img: HTMLCanvasElement | ImageBitmap, opts: IAddImageOpts): number {
     // never allow storage to exceed memory limit
     this._evictOldest(img.width * img.height);
 
@@ -263,7 +269,7 @@ export class ImageStorage implements IDisposable {
     let offset = originX;
     let tileCount = 0;
 
-    if (!scrolling) {
+    if (!opts.scrolling) {
       buffer.x = 0;
       buffer.y = 0;
       offset = 0;
@@ -277,7 +283,7 @@ export class ImageStorage implements IDisposable {
         this._writeToCell(line as IBufferLineExt, offset + col, imageId, row * cols + col);
         tileCount++;
       }
-      if (scrolling) {
+      if (opts.scrolling) {
         if (row < rows - 1) this._terminal._core._inputHandler.lineFeed();
       } else {
         if (++buffer.y >= termRows) break;
@@ -287,8 +293,12 @@ export class ImageStorage implements IDisposable {
     this._terminal._core._inputHandler._dirtyRowTracker.markDirty(buffer.y);
 
     // cursor positioning modes
-    if (scrolling) {
+    if (opts.scrolling) {
-      buffer.x = offset;
+      if (opts.cursorPos === 'iip') {
+        buffer.x = Math.min(offset + cols, termCols);
+      } else {
+        buffer.x = offset;
+      }
     } else {
       buffer.x = originX;
       buffer.y = originY;
@@ -331,8 +341,8 @@ export class ImageStorage implements IDisposable {
       marker: endMarker || undefined,
       tileCount,
       bufferType: this._terminal.buffer.active.type,
-      layer,
+      layer: opts.layer,
-      zIndex
+      zIndex: opts.zIndex
     };
 
     // finally add the image
@@ -455,7 +465,6 @@ export class ImageStorage implements IDisposable {
             if (!nextE || nextE.imageId !== imageId || nextE.tileId !== startTile + count) {
               break;
             }
-            e = nextE;
             count++;
           }
           col--;

addons/addon-image/src/SixelImageStorage.ts

@@ -4,7 +4,7 @@
  */
 
 import { ImageStorage, CELL_SIZE_DEFAULT } from './ImageStorage';
-import { IImageAddonOptions, ITerminalExt } from './Types';
+import { IImageAddonOptions, ITerminalExt, IAddImageOpts } from './Types';
 import { ImageRenderer } from './ImageRenderer';
 
 /**
@@ -15,6 +15,7 @@ import { ImageRenderer } from './ImageRenderer';
  * - advanceCursor for empty sixels carrying only height
  */
 export class SixelImageStorage {
+  private _addImageOpts: IAddImageOpts = { scrolling: true, layer: 'top', zIndex: 0, cursorPos: 'vt340' };
   constructor(
     private readonly _storage: ImageStorage,
     private readonly _opts: IImageAddonOptions,
@@ -27,7 +28,8 @@ export class SixelImageStorage {
    * Cursor behavior depends on the sixelScrolling option (DECSET 80).
    */
   public addImage(img: HTMLCanvasElement | ImageBitmap): void {
-    this._storage.addImage(img, this._opts.sixelScrolling);
+    this._addImageOpts.scrolling = this._opts.sixelScrolling;
+    this._storage.addImage(img, this._addImageOpts);
   }
 
   /**

addons/addon-image/src/Types.ts

@@ -100,6 +100,14 @@ export interface ICellSize {
 }
 
 export type ImageLayer = 'top' | 'bottom';
+export type CursorPos = 'vt340' | 'iip';
+
+export interface IAddImageOpts {
+  scrolling: boolean;
+  layer: ImageLayer;
+  zIndex: number;
+  cursorPos: CursorPos;
+}
 
 export interface IImageSpec {
   orig: HTMLCanvasElement | ImageBitmap | undefined;

addons/addon-image/src/kitty/KittyImageStorage.ts

@@ -5,7 +5,7 @@
 
 import { IDisposable } from '@xterm/xterm';
 import { ImageStorage } from '../ImageStorage';
-import { ImageLayer } from '../Types';
+import { ImageLayer, IAddImageOpts } from '../Types';
 import { IKittyImageData } from './KittyGraphicsTypes';
 
 // Kitty-specific image storage controller.
@@ -42,6 +42,7 @@ export class KittyImageStorage implements IDisposable {
       this._images.delete(kittyId);
     }
   };
+  private _addImageOpts: IAddImageOpts = { scrolling: true, layer: 'top', zIndex: 0, cursorPos: 'iip' };
 
   constructor(
     private readonly _storage: ImageStorage
@@ -98,7 +99,10 @@ export class KittyImageStorage implements IDisposable {
     if (oldStorageId !== undefined) {
       this._storageIdToKittyId.delete(oldStorageId);
     }
-    const storageId = this._storage.addImage(image, scrolling, layer, zIndex);
+    this._addImageOpts.scrolling = scrolling;
+    this._addImageOpts.layer = layer;
+    this._addImageOpts.zIndex = zIndex;
+    const storageId = this._storage.addImage(image, this._addImageOpts);
     this._kittyIdToStorageId.set(kittyId, storageId);
     this._storageIdToKittyId.set(storageId, kittyId);
   }

addons/addon-image/test/ImageAddon.test.ts

@@ -290,6 +290,67 @@ test.describe('ImageAddon', () => {
     });
   });
 
+  test.describe('IIP support', () => {
+    test('size params is optional/informative', async () => {
+      // too small size param
+      await ctx.proxy.write(`\x1b]1337;File=inline=1;size=5:${PALETTE_PNG_BASE64}\x07`);
+      deepStrictEqual(await getOrigSize(1), [640, 80]);
+      // no size aparm at all
+      await ctx.proxy.write(`\x1b[10H\x1b]1337;File=inline=1:${PALETTE_QOI_BASE64}\x07`);
+      deepStrictEqual(await getOrigSize(2), [640, 80]);
+    });
+    test.skip('FilePart support - bytewise', async () => {
+      // opener
+      await ctx.proxy.write(`\x1b]1337;MultipartFile=inline=1\x07`);
+      // byte-wise
+      for (let i = 0; i < PALETTE_PNG_BASE64.length; ++i) {
+        await ctx.proxy.write(`\x1b]1337;FilePart=${PALETTE_PNG_BASE64[i]}\x07`);
+      }
+      // finalizer
+      await ctx.proxy.write(`\x1b]1337;FileEnd\x07`);
+      deepStrictEqual(await getOrigSize(1), [640, 80]);
+    });
+    test('FilePart support - chunks', async () => {
+      // opener
+      await ctx.proxy.write(`\x1b]1337;MultipartFile=inline=1\x07`);
+      // chunks
+      for (let i = 0; i < PALETTE_PNG_BASE64.length; i += 256) {
+        await ctx.proxy.write(`\x1b]1337;FilePart=${PALETTE_PNG_BASE64.slice(i, i + 256)}\x07`);
+      }
+      // finalizer
+      await ctx.proxy.write(`\x1b]1337;FileEnd\x07`);
+      deepStrictEqual(await getOrigSize(1), [640, 80]);
+    });
+    test('FilePart support - edgecases', async () => {
+      // multiple opener do not harm
+      for (let i = 0; i < 10; ++i) {
+        await ctx.proxy.write(`\x1b]1337;MultipartFile=inline=1\x07`);
+      }
+      // multiple finalizer do not harm
+      for (let i = 0; i < 5; ++i) {
+        await ctx.proxy.write(`\x1b]1337;FileEnd\x07`);
+      }
+      // chunks w'o opener are ignored
+      for (let i = 0; i < PALETTE_PNG_BASE64.length; i += 256) {
+        await ctx.proxy.write(`\x1b]1337;FilePart=${PALETTE_PNG_BASE64.slice(i, i + 256)}\x07`);
+      }
+      await ctx.proxy.write(`\x1b]1337;FileEnd\x07`);
+      pollFor(ctx.page, 'window.imageAddon._storage._images.size', 0);
+    });
+    test('FilePart support - other IIP sequence cancels chunked image', async () => {
+      // opener
+      await ctx.proxy.write(`\x1b]1337;MultipartFile=inline=1\x07`);
+      // chunks
+      for (let i = 0; i < PALETTE_PNG_BASE64.length; i += 256) {
+        await ctx.proxy.write(`\x1b]1337;FilePart=${PALETTE_PNG_BASE64.slice(i, i + 256)}\x07`);
+      }
+      // finalizer skipped
+      // write spinfox.png
+      await ctx.proxy.write(TESTDATA_IIP[1][0]);
+      deepStrictEqual(await getOrigSize(1), TESTDATA_IIP[1][1]);
+    });
+  });
+
   test.describe('IIP support - testimages', () => {
     test('palette.png', async () => {
       await ctx.proxy.write(TESTDATA_IIP[0][0]);

addons/addon-image/test/KittyGraphics.test.ts

@@ -539,7 +539,6 @@ test.describe('Kitty Graphics Protocol', () => {
 
   test.describe('Query support (a=q)', () => {
     test('responds with OK for capability query without payload', async () => {
-      let response = '';
       await ctx.page.evaluate(() => {
         (window as any).kittyResponse = '';
         (window as any).term.onData((data: string) => { (window as any).kittyResponse = data; });
@@ -548,12 +547,11 @@ test.describe('Kitty Graphics Protocol', () => {
       await ctx.proxy.write('\x1b_Gi=31,a=q;\x1b\\');
       await timeout(100);
 
-      response = await ctx.page.evaluate('window.kittyResponse');
+      const response = await ctx.page.evaluate('window.kittyResponse');
       strictEqual(response, '\x1b_Gi=31;OK\x1b\\');
     });
 
     test('responds with OK for valid PNG query', async () => {
-      let response = '';
       await ctx.page.evaluate(() => {
         (window as any).kittyResponse = '';
         (window as any).term.onData((data: string) => { (window as any).kittyResponse = data; });
@@ -562,7 +560,7 @@ test.describe('Kitty Graphics Protocol', () => {
       await ctx.proxy.write(`\x1b_Gi=42,a=q,f=100;${KITTY_BLACK_1X1_BASE64}\x1b\\`);
       await timeout(100);
 
-      response = await ctx.page.evaluate('window.kittyResponse');
+      const response = await ctx.page.evaluate('window.kittyResponse');
       strictEqual(response, '\x1b_Gi=42;OK\x1b\\');
     });
 
@@ -578,7 +576,6 @@ test.describe('Kitty Graphics Protocol', () => {
     });
 
     test('responds with error for invalid base64', async () => {
-      let response = '';
       await ctx.page.evaluate(() => {
         (window as any).kittyResponse = '';
         (window as any).term.onData((data: string) => { (window as any).kittyResponse = data; });
@@ -587,12 +584,11 @@ test.describe('Kitty Graphics Protocol', () => {
       await ctx.proxy.write('\x1b_Gi=60,a=q,f=100;!!!invalid!!!\x1b\\');
       await timeout(100);
 
-      response = await ctx.page.evaluate('window.kittyResponse');
+      const response: string = await ctx.page.evaluate('window.kittyResponse');
       strictEqual(response.startsWith('\x1b_Gi=60;EINVAL:'), true);
     });
 
     test('responds with error for RGB data without dimensions', async () => {
-      let response = '';
       await ctx.page.evaluate(() => {
         (window as any).kittyResponse = '';
         (window as any).term.onData((data: string) => { (window as any).kittyResponse = data; });
@@ -601,7 +597,7 @@ test.describe('Kitty Graphics Protocol', () => {
       await ctx.proxy.write('\x1b_Gi=70,a=q,f=24;AAAA\x1b\\');
       await timeout(100);
 
-      response = await ctx.page.evaluate('window.kittyResponse');
+      const response = await ctx.page.evaluate('window.kittyResponse');
       strictEqual(response, '\x1b_Gi=70;EINVAL:width and height required for raw pixel data\x1b\\');
     });
 
@@ -642,7 +638,6 @@ test.describe('Kitty Graphics Protocol', () => {
     });
 
     test('responds with EINVAL when both i and I keys are specified', async () => {
-      let response = '';
       await ctx.page.evaluate(() => {
         (window as any).kittyResponse = '';
         (window as any).term.onData((data: string) => { (window as any).kittyResponse = data; });
@@ -652,12 +647,11 @@ test.describe('Kitty Graphics Protocol', () => {
       await ctx.proxy.write(`\x1b_Gi=100,I=200,a=q,f=100;${KITTY_BLACK_1X1_BASE64}\x1b\\`);
       await timeout(100);
 
-      response = await ctx.page.evaluate('window.kittyResponse');
+      const response = await ctx.page.evaluate('window.kittyResponse');
       strictEqual(response, '\x1b_Gi=100;EINVAL:cannot specify both i and I keys\x1b\\');
     });
 
     test('responds with EINVAL for i+I conflict even without payload', async () => {
-      let response = '';
       await ctx.page.evaluate(() => {
         (window as any).kittyResponse = '';
         (window as any).term.onData((data: string) => { (window as any).kittyResponse = data; });
@@ -667,7 +661,7 @@ test.describe('Kitty Graphics Protocol', () => {
       await ctx.proxy.write('\x1b_Gi=101,I=201,a=d\x1b\\');
       await timeout(100);
 
-      response = await ctx.page.evaluate('window.kittyResponse');
+      const response = await ctx.page.evaluate('window.kittyResponse');
       strictEqual(response, '\x1b_Gi=101;EINVAL:cannot specify both i and I keys\x1b\\');
     });
   });

addons/addon-ligatures/package.json

@@ -31,15 +31,11 @@
   ],
   "license": "MIT",
   "dependencies": {
-    "lru-cache": "^6.0.0",
+    "lru-cache": "^11.3.6",
-    "opentype.js": "^0.8.0"
+    "opentype.js": "^2.0.0"
   },
   "devDependencies": {
-    "@types/lru-cache": "^5.1.0",
+    "@types/opentype.js": "^1.3.9",
-    "@types/opentype.js": "^0.7.0",
+    "font-finder": "^1.1.0"
-    "axios": "^1.15.2",
-    "font-finder": "^1.1.0",
-    "mkdirp": "0.5.5",
-    "yauzl": "^3.2.1"
   }
 }

addons/addon-ligatures/src/fontLigatures/index.ts

@@ -1,5 +1,5 @@
 import * as opentype from 'opentype.js';
-import LRUCache = require('lru-cache');
+import { LRUCache } from 'lru-cache';
 
 import { IFont, ILigatureData, IFlattenedLookupTree, ILookupTree, IOptions } from './types';
 import mergeTrees from './merge';
@@ -23,8 +23,8 @@ class FontImpl implements IFont {
 
     if (options.cacheSize > 0) {
       this._cache = new LRUCache({
-        max: options.cacheSize,
+        maxSize: options.cacheSize,
-        length: ((val: ILigatureData | [number, number][], key: string) => key.length) as any
+        sizeCalculation: ((val: ILigatureData | [number, number][], key: string) => key.length) as any
       });
     }
 

addons/addon-ligatures/src/fontLigatures/mergeRange.ts

@@ -44,7 +44,6 @@ export default function mergeRange(ranges: [number, number][], newRangeStart: nu
         // current range
         ranges[i - 1][1] = Math.max(newRangeEnd, range[1]);
         ranges.splice(i, 1);
-        inRange = false;
         return ranges;
       }
       // Case 7: New range extends from previous range past the

addons/addon-progress/test/ProgressAddon.test.ts

@@ -9,15 +9,18 @@ import { ITestContext, createTestContext, openTerminal } from '../../../test/pla
 
 
 let ctx: ITestContext;
-test.beforeAll(async ({ browser }) => {
-  ctx = await createTestContext(browser);
-  ctx.page.setViewportSize({ width: 1024, height: 768 });
-  await openTerminal(ctx);
-});
-test.afterAll(async () => await ctx.page.close());
-
 
 test.describe('ProgressAddon', () => {
+  test.describe.configure({ mode: 'serial' });
+
+  test.beforeAll(async ({ browser }) => {
+    ctx = await createTestContext(browser);
+    await openTerminal(ctx);
+  });
+  test.afterAll(async () => {
+    await ctx?.page?.close();
+  });
+
   test.beforeEach(async function(): Promise<any> {
     await ctx.page.evaluate(`
       window.progressStack = [];

addons/addon-search/src/SearchEngine.ts

@@ -174,7 +174,7 @@ export class SearchEngine {
     this._terminal.clearSelection();
 
     let startRow = this._terminal.buffer.active.baseY + this._terminal.rows - 1;
-    let startCol = this._terminal.cols;
+    const startCol = this._terminal.cols;
     const isReverseSearch = true;
 
     this._lineCache.initLinesCache();
@@ -186,14 +186,14 @@ export class SearchEngine {
     let result: ISearchResult | undefined;
     if (prevSelectedPos) {
       searchPosition.startRow = startRow = prevSelectedPos.start.y;
-      searchPosition.startCol = startCol = prevSelectedPos.start.x;
+      searchPosition.startCol = prevSelectedPos.start.x;
       if (cachedSearchTerm !== term) {
         // Try to expand selection to right first.
         result = this._findInLine(term, searchPosition, searchOptions, false);
         if (!result) {
           // If selection was not able to be expanded to the right, then try reverse search
           searchPosition.startRow = startRow = prevSelectedPos.end.y;
-          searchPosition.startCol = startCol = prevSelectedPos.end.x;
+          searchPosition.startCol = prevSelectedPos.end.x;
         }
       }
     }

addons/addon-serialize/benchmark/tsconfig.json

@@ -7,10 +7,10 @@
     "rootDir": "..",
     "outDir": "../out-benchmark",
     "types": ["../../../node_modules/@types/node"],
-    "moduleResolution": "node",
+    "moduleResolution": "nodenext",
     "strict": false,
     "target": "es2021",
-    "module": "commonjs",
+    "module": "nodenext",
     "paths": {
       "common/*": ["../../../src/common/*"],
       "browser/*": ["../../../src/browser/*"],

addons/addon-unicode-graphemes/benchmark/tsconfig.json

@@ -4,10 +4,10 @@
     "rootDir": "..",
     "outDir": "../out-benchmark",
     "types": ["../../../node_modules/@types/node"],
-    "moduleResolution": "node",
+    "moduleResolution": "nodenext",
     "strict": false,
     "target": "es2015",
-    "module": "commonjs",
+    "module": "nodenext",
     "paths": {
       "common/*": ["../../../src/common/*"],
       "browser/*": ["../../../src/browser/*"],

addons/addon-web-fonts/test/WebFontsAddon.test.ts

@@ -78,7 +78,22 @@ test.describe('WebFontsAddon', () => {
       const data = await ctx.page.evaluate(`
           document.styleSheets[0].insertRule("@font-face {font-family: Kongtext; src: url(/fonts/kongtext.regular.ttf) format('truetype'); unicode-range: U+00A0-00FF}", 0);
         `);
-      deepStrictEqual(await getDocumentFonts(), [{ family: 'Kongtext', status: 'unloaded' }]);
+      let fonts = await getDocumentFonts();
+      // safari may have loaded the font, firefox & chrome never load it
+      if (browser.browserType().name() === 'webkit') {
+        try {
+          deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'loading' }]);
+        } catch (e) {
+          try {
+            deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'loaded' }]);
+          } catch (e) {
+            deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'unloaded' }]);
+          }
+        }
+      } else {
+        deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'unloaded' }]);
+      }
+
 
       // broken case: webfont in ctor without addon usage
       await ctx.page.evaluate(`
@@ -86,15 +101,20 @@ test.describe('WebFontsAddon', () => {
           window.helperTerm.open(term.element);
         `);
 
-      // safari loads the font, firefox & chrome dont
+      fonts = await getDocumentFonts();
+      // safari might load the font, firefox & chrome dont
       if (browser.browserType().name() === 'webkit') {
         try {
-          deepStrictEqual(await getDocumentFonts(), [{ family: 'Kongtext', status: 'loading' }]);
+          deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'loading' }]);
         } catch (e) {
-          deepStrictEqual(await getDocumentFonts(), [{ family: 'Kongtext', status: 'loaded' }]);
+          try {
+            deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'loaded' }]);
+          } catch (e) {
+            deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'unloaded' }]);
+          }
         }
       } else {
-        deepStrictEqual(await getDocumentFonts(), [{ family: 'Kongtext', status: 'unloaded' }]);
+        deepStrictEqual(fonts, [{ family: 'Kongtext', status: 'unloaded' }]);
       }
 
       // good case: addon fixes layout for webfont in ctor

addons/addon-web-fonts/test/tsconfig.json

@@ -5,7 +5,6 @@
     "lib": [
       "es2021",
     ],
-    // "downlevelIteration": true,
     "rootDir": ".",
     "outDir": "../out-test",
     "sourceMap": true,

addons/addon-web-links/src/WebLinkProvider.ts

@@ -113,8 +113,8 @@ export class LinkComputer {
     let line: IBufferLine | undefined;
     let topIdx = lineIndex;
     let bottomIdx = lineIndex;
-    let length = 0;
+    let length;
-    let content = '';
+    let content;
     const lines: string[] = [];
 
     if ((line = terminal.buffer.active.getLine(lineIndex))) {

addons/addon-web-links/test/tsconfig.json

@@ -5,7 +5,6 @@
     "lib": [
       "es2021",
     ],
-    // "downlevelIteration": true,
     "rootDir": ".",
     "outDir": "../out-test",
     "sourceMap": true,

addons/addon-webgl/src/WebglRenderer.ts

@@ -427,8 +427,8 @@ export class WebglRenderer extends Disposable implements IRenderer {
     let line: IBufferLine;
     let joinedRanges: [number, number][];
     let isJoined: boolean;
-    let skipJoinedCheckUntilX: number = 0;
+    let skipJoinedCheckUntilX: number;
-    let isValidJoinRange: boolean = true;
+    let isValidJoinRange: boolean;
     let lastCharX: number;
     let range: [number, number];
     let isCursorRow: boolean;

addons/addon-webgl/src/tsconfig.json

@@ -25,7 +25,6 @@
       ]
     },
     "strict": true,
-    "downlevelIteration": true,
     "experimentalDecorators": true,
     "types": [
       "../../../node_modules/@types/mocha"

demo/client/components/window/addonImageWindow.ts

@@ -65,7 +65,8 @@ export class AddonImageWindow extends BaseWindow implements IControlWindow {
     const dtIip = document.createElement('dt');
     dtIip.textContent = 'IIP (iTerm)';
     dlIip.appendChild(dtIip);
-    this._addDdWithButton(dlIip, 'image-demo3', 'palette');
+    this._addDdWithButton(dlIip, 'image-demo3', 'palette (png File)');
+    this._addDdWithButton(dlIip, 'image-demo4', 'dice (qoi MultipartFile)');
     container.appendChild(dlIip);
 
     // Kitty demos
@@ -141,6 +142,21 @@ export class AddonImageWindow extends BaseWindow implements IControlWindow {
         this._terminal.write(`\x1b]1337;File=inline=1;size=${data.length}:${btoa(sdata)}\x1b\\`);
       });
 
+    const iipDemoMulti = (url: string) => () => fetch(url)
+      .then(resp => resp.arrayBuffer())
+      .then(buffer => {
+        const data = new Uint8Array(buffer);
+        let sdata = '';
+        for (let i = 0; i < data.length; ++i) sdata += String.fromCharCode(data[i]);
+        const encoded = btoa(sdata);
+        this._terminal.write('\r\n');
+        this._terminal.write(`\x1b]1337;MultipartFile=inline=1\x1b\\`);
+        for (let i = 0; i < encoded.length; i += 100) {
+          this._terminal.write(`\x1b]1337;FilePart=${encoded.slice(i, i + 100)}\x1b\\`);
+        }
+        this._terminal.write(`\x1b]1337;FileEnd\x1b\\`);
+      });
+
     const kittyDemo = (url: string) => () => fetch(url)
       .then(resp => resp.arrayBuffer())
       .then(buffer => {
@@ -158,6 +174,8 @@ export class AddonImageWindow extends BaseWindow implements IControlWindow {
       sixelDemo('https://raw.githubusercontent.com/jerch/node-sixel/master/testfiles/test2.sixel'));
     document.getElementById('image-demo3')!.addEventListener('click',
       iipDemo('https://raw.githubusercontent.com/jerch/node-sixel/master/palette.png'));
+    document.getElementById('image-demo4')!.addEventListener('click',
+      iipDemoMulti('https://raw.githubusercontent.com/jerch/xterm-wasm-parts/master/fixtures/qoi/dice.qoi'));
     document.getElementById('image-demo-kitty1')!.addEventListener('click',
       kittyDemo('https://raw.githubusercontent.com/jerch/node-sixel/master/palette.png'));
 
@@ -176,7 +194,7 @@ export class AddonImageWindow extends BaseWindow implements IControlWindow {
       //   }
       // }
 
-      const pos = (this._terminal as any)._core._mouseService!.getCoords(ev, (this._terminal as any)._core.screenElement!, this._terminal.cols, this._terminal.rows);
+      const pos = (this._terminal as any)._core._mouseCoordsService!.getCoords(ev, (this._terminal as any)._core.screenElement!, this._terminal.cols, this._terminal.rows);
       const x = pos[0] - 1;
       const y = pos[1] - 1;
       const canvas = ev.shiftKey

demo/client/tsconfig.json

@@ -2,6 +2,7 @@
   "compilerOptions": {
     "module": "commonjs",
     "target": "es2021",
+    "types": ["node"],
     "outDir": "../out-demo/client",
     "rootDir": ".",
     "sourceMap": true,

demo/server/server.ts

@@ -118,7 +118,7 @@ function startServer(): void {
   });
 
   appWs.ws('/terminals/:pid', function (ws, req) {
-    const term = terminals[parseInt(req.params.pid)];
+    const term = terminals[parseInt(Array.isArray(req.params.pid) ? req.params.pid[0] : req.params.pid)];
     console.log('Connected to terminal ' + term.pid);
     temporaryDisposable[term.pid].dispose();
     delete temporaryDisposable[term.pid];

eslint.config.mjs

@@ -37,7 +37,7 @@ export default tseslint.config(
       '@stylistic/comma-spacing': ['warn', { before: false, after: true }],
       '@stylistic/indent': ['warn', 2],
       '@stylistic/semi': ['warn', 'always'],
-      '@stylistic/quotes': ['warn', 'single', { allowTemplateLiterals: true }],
+      '@stylistic/quotes': ['warn', 'single', { allowTemplateLiterals: 'always' }],
       '@stylistic/member-delimiter-style': ['warn', {
         multiline: { delimiter: 'semi', requireLast: true },
         singleline: { delimiter: 'comma', requireLast: false }

eslint.config.typings.mjs

@@ -17,7 +17,7 @@ export default tseslint.config(
     rules: {
       '@stylistic/indent': ['warn', 2],
       '@stylistic/semi': ['warn', 'always'],
-      '@stylistic/quotes': ['warn', 'single', { allowTemplateLiterals: true }],
+      '@stylistic/quotes': ['warn', 'single', { allowTemplateLiterals: 'always' }],
       '@stylistic/member-delimiter-style': ['warn', {
         multiline: { delimiter: 'semi', requireLast: true },
         singleline: { delimiter: 'comma', requireLast: false }

package.json

@@ -75,40 +75,41 @@
     "prepublishOnly": "npm run package"
   },
   "devDependencies": {
+    "@eslint/js": "^10.0.1",
     "@lunapaint/png-codec": "^0.2.0",
-    "@playwright/test": "^1.57.0",
+    "@playwright/test": "^1.59.1",
-    "@stylistic/eslint-plugin": "^4.4.1",
+    "@stylistic/eslint-plugin": "^5.10.0",
-    "@types/chai": "^4.2.22",
+    "@types/chai": "^5.2.3",
-    "@types/express": "4",
+    "@types/express": "^5.0.6",
     "@types/express-ws": "^3.0.1",
-    "@types/jsdom": "^27.0.0",
+    "@types/jsdom": "^28.0.1",
-    "@types/mocha": "^9.0.0",
+    "@types/mocha": "^10.0.10",
     "@types/node": "^22.19.3",
     "@types/webpack": "^5.28.0",
     "@types/ws": "^8.2.0",
-    "@typescript-eslint/eslint-plugin": "^8.50.1",
+    "@typescript-eslint/eslint-plugin": "^8.59.2",
-    "@typescript-eslint/parser": "^8.50.1",
+    "@typescript-eslint/parser": "^8.59.2",
-    "@typescript/native-preview": "^7.0.0-dev.20260213.1",
+    "@typescript/native-preview": "^7.0.0-dev.20260509.2",
-    "chai": "^4.3.4",
+    "chai": "^6.2.2",
     "concurrently": "^9.1.2",
-    "esbuild": "~0.25.2",
+    "esbuild": "^0.28.0",
-    "eslint": "^9.39.2",
+    "eslint": "^10.3.0",
-    "eslint-plugin-jsdoc": "^50.8.0",
+    "eslint-plugin-jsdoc": "^62.9.0",
-    "express": "^4.19.2",
+    "express": "^5.2.1",
     "express-ws": "^5.0.2",
-    "jsdom": "^27.3.0",
+    "jsdom": "^29.1.1",
-    "mocha": "^10.1.0",
+    "mocha": "^11.7.5",
     "mustache": "^4.2.0",
     "node-pty": "^1.2.0-beta.9",
-    "nyc": "^17.1.0",
+    "nyc": "^18.0.0",
-    "source-map-loader": "^3.0.0",
+    "source-map-loader": "^5.0.0",
     "source-map-support": "^0.5.20",
-    "ts-loader": "^9.3.1",
+    "ts-loader": "^9.5.7",
     "typescript": "^5.9.3",
-    "typescript-eslint": "^8.50.1",
+    "typescript-eslint": "^8.59.2",
-    "webpack": "^5.61.0",
+    "webpack": "^5.106.2",
-    "webpack-cli": "^4.9.1",
+    "webpack-cli": "^7.0.2",
-    "ws": "^8.2.3",
+    "ws": "^8.20.0",
-    "xterm-benchmark": "^0.3.1"
+    "xterm-benchmark": "^0.3.2"
   }
 }

src/browser/CoreBrowserTerminal.ts

@@ -37,7 +37,7 @@ import { CharacterJoinerService } from 'browser/services/CharacterJoinerService'
 import { CoreBrowserService } from 'browser/services/CoreBrowserService';
 import { LinkProviderService } from 'browser/services/LinkProviderService';
 import { MouseCoordsService } from 'browser/services/MouseCoordsService';
-import { MouseService } from 'browser/services/MouseService';
+import { MouseEventCssClasses, MouseService } from 'browser/services/MouseService';
 import { RenderService } from 'browser/services/RenderService';
 import { SelectionService } from 'browser/services/SelectionService';
 import { ICharSizeService, ICharacterJoinerService, ICoreBrowserService, IKeyboardService, ILinkProviderService, IMouseCoordsService, IMouseService, IRenderService, ISelectionService, IThemeService } from 'browser/services/Services';
@@ -212,7 +212,7 @@ export class CoreBrowserTerminal extends CoreTerminal implements ITerminal {
     if (!this._themeService) return;
     for (const req of event) {
       let acc: 'foreground' | 'background' | 'cursor' | 'ansi';
-      let ident = '';
+      let ident: string;
       switch (req.index) {
         case SpecialColorIndex.FOREGROUND: // OSC 10 | 110
           acc = 'foreground';
@@ -618,11 +618,12 @@ export class CoreBrowserTerminal extends CoreTerminal implements ITerminal {
     this._register(addDisposableListener(this.element, 'mousedown', (e: MouseEvent) => this._selectionService!.handleMouseDown(e)));
 
     // apply mouse event classes set by escape codes before terminal was attached
-    if (this.mouseStateService.areMouseEventsActive) {
+    if (this.mouseStateService.areMouseEventsActive && !this.options.mouseEventsRequireAlt) {
       this._selectionService.disable();
-      this.element.classList.add('enable-mouse-events');
+      this.element.classList.add(MouseEventCssClasses.ENABLE_MOUSE_EVENTS);
     } else {
       this._selectionService.enable();
+      this.element.classList.remove(MouseEventCssClasses.ENABLE_MOUSE_EVENTS);
     }
 
     if (this.options.screenReaderMode) {

src/browser/REARCHITECTURE.md

@@ -0,0 +1,173 @@
+# Browser folder rearchitecture
+
+Composite TypeScript projects with enforced dependencies, mirroring the layered layout planned for `src/common/`.
+
+## Platform layer rule
+
+A module is **platform** only if **no class** in that project has a **service** injected via its constructor. That includes:
+
+- Common services (`@IBufferService`, `@IOptionsService`, `@ICoreService`, `@IInstantiationService`, etc.)
+- Browser services (`@ICoreBrowserService`, `@IRenderService`, `@IThemeService`, `@ICharSizeService`, …)
+
+Passing a service into a **function** (e.g. `moveToCellSequence(…, bufferService)`) is fine. `new TextBlinkStateManager(…, coreBrowserService, optionsService)` is not — that class belongs in integration.
+
+Interface-only modules (`browser/selection/Types.ts`, `renderer/shared/Types.ts`) are platform. Implementations that take services are not.
+
+## Dependency graph (corrected)
+
+```mermaid
+flowchart BT
+  subgraph platform["Platform layer — no ctor service injection"]
+    direction LR
+    base["browser/base"]
+    scrollable["browser/scrollable"]
+    input["browser/input"]
+    selectionTypes["browser/selection/types"]
+    renderCore["browser/renderer/core"]
+    decorStore["browser/decorations/store"]
+
+    scrollable --> base
+    input --> base
+    selectionTypes --> base
+    renderCore --> base
+    decorStore --> base
+  end
+
+  subgraph integration["Integration layer — DI and wiring"]
+    direction LR
+    services["browser/services"]
+    renderer["browser/renderer"]
+    decorations["browser/decorations"]
+    terminal["browser/terminal"]
+
+    services --> base
+    services --> input
+    services --> selectionTypes
+    services --> renderCore
+    services --> decorStore
+    renderer --> services
+    renderer --> renderCore
+    renderer --> base
+    decorations --> services
+    decorations --> decorStore
+    decorations --> renderCore
+    terminal --> services
+    terminal --> renderer
+    terminal --> decorations
+    terminal --> input
+    terminal --> scrollable
+    terminal --> base
+  end
+
+  subgraph api_layer["API layer"]
+    public["browser/public"]
+  end
+
+  integration --> platform
+  api_layer --> integration
+
+  public --> terminal
+```
+
+`browser/renderer` is **not** platform: it owns `DomRenderer`, `DomRendererRowFactory`, and `TextBlinkStateManager`, all of which take injected services.
+
+## Constructor audit (current tree)
+
+### Platform-eligible
+
+| Location | Type | Notes |
+| --- | --- | --- |
+| `Dom.ts`, `Types.ts`, `LocalizableStrings.ts`, `ColorContrastCache.ts`, `TimeBasedDebouncer.ts`, `shared/` | classes / functions | no DI |
+| `scrollable/**` | widgets | `touch.ts` uses `Dom` only |
+| `input/Mouse.ts` | functions | pure DOM math |
+| `input/MoveToCell.ts` | functions | `IBufferService` passed as argument, not ctor-injected |
+| `selection/Types.ts` | interfaces | no classes with DI |
+| `renderer/shared/Constants.ts`, `RendererUtils.ts`, `Types.ts`, `SelectionRenderModel.ts` | classes | no DI |
+| `renderer/dom/WidthCache.ts` | class | canvas factory only, no services |
+| `decorations/ColorZoneStore.ts` | class | common types only, no DI |
+
+### Integration-only (ctor service injection)
+
+| Location | Injected services (representative) |
+| --- | --- |
+| `selection/SelectionModel.ts` | `IBufferService` |
+| `input/CompositionHelper.ts` | `IBufferService`, `IOptionsService`, `ICoreService`, `IRenderService` |
+| `renderer/shared/TextBlinkStateManager.ts` | `ICoreBrowserService`, `IOptionsService` |
+| `renderer/dom/DomRendererRowFactory.ts` | `ICharacterJoinerService`, `IOptionsService`, `ICoreBrowserService`, `ICoreService`, `IDecorationService`, `IThemeService` |
+| `renderer/dom/DomRenderer.ts` | `IInstantiationService`, `ICharSizeService`, `IOptionsService`, `IBufferService`, `ICoreService`, `ICoreBrowserService`, `IThemeService`; creates `DomRendererRowFactory` via `IInstantiationService` |
+| `renderer/dom/DomRenderer` inner `CursorBlinkStateManager` | `ICoreBrowserService` |
+| `services/**` | common + browser services (all `@…` ctor params) |
+| `RenderDebouncer.ts` | `ICoreBrowserService` |
+| `decorations/BufferDecorationRenderer.ts`, `OverviewRulerRenderer.ts` | `IBufferService`, `ICoreBrowserService`, `IDecorationService`, `IRenderService`, `IThemeService`, … |
+| `Viewport.ts`, `Linkifier.ts`, `AccessibilityManager.ts`, `OscLinkProvider.ts` | multiple common + browser services |
+| `CoreBrowserTerminal.ts` | orchestrates service registration and renderer construction |
+
+`Clipboard.ts` has no class ctor DI; handlers receive `ISelectionService` at call sites — keep with `terminal`.
+
+## Target package layout
+
+### Platform
+
+| Project | Contents |
+| --- | --- |
+| `browser/base` | `Dom`, `Types`, `LocalizableStrings`, `ColorContrastCache`, `TimeBasedDebouncer`, `shared/`; browser **service interfaces** (extracted from `services/Services.ts`) |
+| `browser/scrollable` | `scrollable/**` |
+| `browser/input` | `Mouse.ts`, `MoveToCell.ts` only |
+| `browser/selection/types` | `selection/Types.ts` (or merge into `base` if preferred) |
+| `browser/renderer/core` | `renderer/shared/{Constants,RendererUtils,Types,SelectionRenderModel}.ts`, `renderer/dom/WidthCache.ts` |
+| `browser/decorations/store` | `ColorZoneStore.ts` |
+
+`SelectionModel` moves to **`browser/services`** (only consumer is `SelectionService`).
+
+`CompositionHelper` moves to **`browser/terminal`** (or `browser/input/ime` as integration sibling).
+
+`TextBlinkStateManager`, `DomRenderer`, `DomRendererRowFactory` move to **`browser/renderer`** (integration), depending on **`browser/services`**.
+
+### Integration
+
+| Project | Contents |
+| --- | --- |
+| `browser/services` | `services/**`, `selection/SelectionModel.ts`, `RenderDebouncer.ts` |
+| `browser/renderer` | `TextBlinkStateManager.ts`, `renderer/dom/DomRenderer.ts`, `DomRendererRowFactory.ts` (+ tests) |
+| `browser/decorations` | `BufferDecorationRenderer.ts`, `OverviewRulerRenderer.ts` |
+| `browser/terminal` | `CoreBrowserTerminal.ts`, `Viewport.ts`, `Linkifier.ts`, `Clipboard.ts`, `AccessibilityManager.ts`, `OscLinkProvider.ts`, `CompositionHelper.ts` |
+
+### API
+
+| Project | Contents |
+| --- | --- |
+| `browser/public` | `public/Terminal.ts` |
+
+## Build order
+
+1. `base`, `scrollable`, `input`, `selection/types`, `renderer/core`, `decorations/store`
+2. `services`
+3. `renderer`, `decorations`
+4. `terminal`
+5. `public`
+
+## Why `renderer/dom` is not platform
+
+`DomRenderer` (abbreviated):
+
+```ts
+constructor(
+  …,
+  @IInstantiationService instantiationService: IInstantiationService,
+  @ICharSizeService private readonly _charSizeService: ICharSizeService,
+  @IOptionsService private readonly _optionsService: IOptionsService,
+  @IBufferService private readonly _bufferService: IBufferService,
+  @ICoreService private readonly _coreService: ICoreService,
+  @ICoreBrowserService private readonly _coreBrowserService: ICoreBrowserService,
+  @IThemeService private readonly _themeService: IThemeService
+) {
+  this._rowFactory = instantiationService.createInstance(DomRendererRowFactory, document);
+  this._textBlinkStateManager = this._register(new TextBlinkStateManager(…, this._coreBrowserService, this._optionsService));
+}
+```
+
+`DomRendererRowFactory` similarly injects `ICharacterJoinerService`, `ICoreBrowserService`, `IThemeService`, and other services. So **`renderer/dom` → `browser/services`** (and common services) today; the corrected graph places the whole DOM renderer stack in integration, with only `WidthCache` left in `renderer/core`.
+
+## Parity with `common/`
+
+Common platform modules contain algorithms and data structures without terminal service wiring. Browser platform modules are the same: DOM/scroll utilities, pointer math, renderer **primitives** (`WidthCache`, selection render geometry), and shared types — not renderers or IME helpers that pull `IRenderService` / `IThemeService` from DI.

src/browser/Terminal2.test.ts

@@ -14,7 +14,7 @@ import { IDisposable } from '@xterm/xterm';
 const COLS = 80;
 const ROWS = 25;
 
-const escapeSequenceFilesDir = path.join(__dirname, '../../fixtures/escape_sequence_files');
+const escapeSequenceFilesDir = path.join(__dirname, '../../test/fixtures/escape_sequence_files');
 const TESTFILES = fs.readdirSync(escapeSequenceFilesDir)
   .filter(f => f.endsWith('.in'))
   .map(f => path.join(escapeSequenceFilesDir, f));
@@ -125,7 +125,7 @@ function formatError(input: string, output: string, expected: string): string {
 // simple debug output of terminal cells
 function terminalToString(term: CoreBrowserTerminal): string {
   let result = '';
-  let lineText = '';
+  let lineText: string;
   for (let line = term.buffer.ybase; line < term.buffer.ybase + term.rows; line++) {
     lineText = term.buffer.lines.get(line)!.translateToString(true);
     // rtrim empty cells as xterm does

src/browser/renderer/dom/DomRendererRowFactory.ts

@@ -90,14 +90,14 @@ export class DomRendererRowFactory {
     let charElement: HTMLSpanElement | undefined;
     let cellAmount = 0;
     let text = '';
-    let i = 0;
+    let i;
     let oldBg = 0;
     let oldFg = 0;
     let oldExt = 0;
     let oldLinkHover: number | boolean = false;
     let oldSpacing = 0;
     let oldIsInSelection: boolean = false;
-    let spacing = 0;
+    let spacing;
     let skipJoinedCheckUntilX = 0;
     const classes: string[] = [];
 
@@ -231,6 +231,7 @@ export class DomRendererRowFactory {
           }
           charElement = this._document.createElement('span');
           cellAmount = 0;
+          // eslint-disable-next-line no-useless-assignment
           text = '';
         }
       }

src/browser/renderer/dom/WidthCache.ts

@@ -110,7 +110,7 @@ export class WidthCache implements IDisposable {
    * `variant` denotes the font variant to be used.
    */
   public get(c: string, bold: boolean | number, italic: boolean | number): number {
-    let cp = 0;
+    let cp: number;
     if (!bold && !italic && c.length === 1 && (cp = c.charCodeAt(0)) < WidthCacheSettings.FLAT_SIZE) {
       if (this._flat[cp] !== WidthCacheSettings.FLAT_UNSET) {
         return this._flat[cp];

src/browser/scrollable/touch.ts

@@ -367,7 +367,7 @@ export class Gesture extends Disposable {
   private _dispatchEvent(event: IGestureEvent): void {
     if (event.type === EventType.TAP) {
       const currentTime = (new Date()).getTime();
-      let setTapCount = 0;
+      let setTapCount;
       if (currentTime - this._lastSetTapCountTime > Gesture._clearTapCountTime) {
         setTapCount = 1;
       } else {

src/browser/services/CharacterJoinerService.test.ts

@@ -285,7 +285,7 @@ function substringJoiner(substring: string): (sequence: string) => [number, numb
   return (sequence: string): [number, number][] => {
     const ranges: [number, number][] = [];
     let searchIndex = 0;
-    let matchIndex = -1;
+    let matchIndex;
 
     while ((matchIndex = sequence.indexOf(substring, searchIndex)) !== -1) {
       const matchEndIndex = matchIndex + substring.length;

src/browser/services/MouseService.test.ts

@@ -3,10 +3,11 @@
  * @license MIT
  */
 import { assert } from 'chai';
-import { MouseService } from 'browser/services/MouseService';
+import { AltMouseCursorController, MouseEventCssClasses, MouseService } from 'browser/services/MouseService';
 import { MouseStateService } from 'common/services/MouseStateService';
 import { CoreMouseAction, CoreMouseButton } from 'common/Types';
 import { IBufferService, ICoreService, ILogService, IOptionsService } from 'common/services/Services';
+import { OptionsService } from 'common/services/OptionsService';
 import { MockCoreBrowserService, MockRenderService, MockSelectionService } from 'browser/TestUtils.test';
 
 function toBytes(s: string | undefined): number[] {
@@ -42,6 +43,36 @@ const logService: ILogService = {
   error: () => {}
 } as any;
 
+class TestSelectionService extends MockSelectionService {
+  public enableCount = 0;
+  public disableCount = 0;
+
+  public override enable(): void {
+    this.enableCount++;
+  }
+
+  public override disable(): void {
+    this.disableCount++;
+  }
+
+  public override shouldForceSelection(): boolean {
+    return false;
+  }
+}
+
+function createTestMouseTargetElement(): HTMLElement {
+  const classes = new Set<string>();
+  return {
+    classList: {
+      add: (className: string) => classes.add(className),
+      remove: (className: string) => classes.delete(className),
+      contains: (className: string) => classes.has(className)
+    },
+    addEventListener: () => {},
+    removeEventListener: () => {}
+  } as any;
+}
+
 describe('MouseService _triggerMouseEvent', () => {
   let mouseService: MouseService;
   let mouseStateService: MouseStateService;
@@ -211,3 +242,112 @@ describe('MouseService _triggerMouseEvent', () => {
     reports = [];
   });
 });
+
+describe('MouseService mouseEventsRequireAlt', () => {
+  it('should update selection state and cursor class when toggled while mouse events are active', () => {
+    const mouseStateService = new MouseStateService();
+    const optionsService = new OptionsService({});
+    const selectionService = new TestSelectionService();
+    const mouseService = new MouseService(
+      new MockRenderService(),
+      {
+        getMouseReportCoords: (_ev: MouseEvent, _el: HTMLElement) => ({ col: 0, row: 0, x: 0, y: 0 })
+      } as any,
+      mouseStateService,
+      {
+        triggerDataEvent: () => {},
+        triggerBinaryEvent: () => {},
+        decPrivateModes: { applicationCursorKeys: false }
+      } as any,
+      bufferService,
+      optionsService,
+      selectionService,
+      logService,
+      new MockCoreBrowserService()
+    );
+    const element = createTestMouseTargetElement();
+    const screenElement = createTestMouseTargetElement();
+    const document = {
+      addEventListener: () => {},
+      removeEventListener: () => {}
+    } as any;
+
+    mouseService.bindMouse({
+      element,
+      screenElement,
+      document
+    }, disposable => disposable, () => {});
+
+    mouseStateService.activeProtocol = 'ANY';
+    assert.isTrue(element.classList.contains(MouseEventCssClasses.ENABLE_MOUSE_EVENTS));
+    assert.equal(selectionService.disableCount, 1);
+
+    optionsService.options.mouseEventsRequireAlt = true;
+    assert.isFalse(element.classList.contains(MouseEventCssClasses.ENABLE_MOUSE_EVENTS));
+    assert.equal(selectionService.enableCount, 2);
+
+    optionsService.options.mouseEventsRequireAlt = false;
+    assert.isTrue(element.classList.contains(MouseEventCssClasses.ENABLE_MOUSE_EVENTS));
+    assert.equal(selectionService.disableCount, 2);
+  });
+
+  it('should strip alt modifier from forwarded mouse reports', () => {
+    const mouseStateService = new MouseStateService();
+    mouseStateService.activeProtocol = 'ANY';
+    mouseStateService.activeEncoding = 'SGR';
+    const optionsService = new OptionsService({ mouseEventsRequireAlt: true });
+    const reports: string[] = [];
+    const mouseService = new MouseService(
+      new MockRenderService(),
+      {
+        getMouseReportCoords: () => ({ col: 0, row: 0, x: 0, y: 0 })
+      } as any,
+      mouseStateService,
+      {
+        triggerDataEvent: (data: string) => reports.push(data),
+        triggerBinaryEvent: () => {},
+        decPrivateModes: { applicationCursorKeys: false }
+      } as any,
+      bufferService,
+      optionsService,
+      new TestSelectionService(),
+      logService,
+      new MockCoreBrowserService()
+    );
+    const ctx = {
+      target: {
+        screenElement: createTestMouseTargetElement()
+      },
+      requestedEvents: {}
+    } as any;
+
+    const sent = (mouseService as any)._sendEvent(ctx, {
+      type: 'mousedown',
+      button: 0,
+      altKey: true,
+      ctrlKey: false,
+      shiftKey: false
+    } as MouseEvent);
+
+    assert.isTrue(sent);
+    assert.deepEqual(reports, ['\x1b[<0;1;1M']);
+  });
+
+  it('should toggle enable-mouse-events class when alt modifier changes', () => {
+    const element = createTestMouseTargetElement();
+    const altMouseCursor = new AltMouseCursorController(element, {
+      addEventListener: () => {},
+      removeEventListener: () => {}
+    } as any, () => true);
+
+    const sync = (altHeld: boolean) => altMouseCursor.syncFromModifier({
+      getModifierState: (key: string) => key === 'Alt' && altHeld
+    } as KeyboardEvent);
+
+    assert.isFalse(element.classList.contains(MouseEventCssClasses.ENABLE_MOUSE_EVENTS));
+    sync(true);
+    assert.isTrue(element.classList.contains(MouseEventCssClasses.ENABLE_MOUSE_EVENTS));
+    sync(false);
+    assert.isFalse(element.classList.contains(MouseEventCssClasses.ENABLE_MOUSE_EVENTS));
+  });
+});

src/browser/services/MouseService.ts

@@ -7,12 +7,16 @@ import { addDisposableListener } from 'browser/Dom';
 import { IBufferService, IMouseStateService, ICoreService, ILogService, IOptionsService } from 'common/services/Services';
 import { CoreMouseAction, CoreMouseButton, CoreMouseEventType, ICoreMouseEvent, IDisposable } from 'common/Types';
 import { C0 } from 'common/data/EscapeSequences';
-import { toDisposable } from 'common/Lifecycle';
+import { DisposableStore, MutableDisposable, toDisposable } from 'common/Lifecycle';
 import { ICoreBrowserService, IMouseCoordsService, IMouseService, IMouseServiceTarget, IRenderService, ISelectionService } from './Services';
 import { Gesture, EventType as GestureEventType, IGestureEvent } from 'browser/scrollable/touch';
 
 type RequestedMouseEvents = Record<'mouseup' | 'wheel' | 'mousedrag' | 'mousemove', EventListener | null>;
 
+export const enum MouseEventCssClasses {
+  ENABLE_MOUSE_EVENTS = 'enable-mouse-events'
+}
+
 interface IMouseBindContext {
   readonly target: IMouseServiceTarget;
   readonly focus: () => void;
@@ -25,6 +29,7 @@ export class MouseService implements IMouseService {
   private _lastEvent: ICoreMouseEvent | null = null;
   private _wheelPartialScroll: number = 0;
   private _touchScrollAccumulator: number = 0;
+  private _altMouseCursor: AltMouseCursorController | undefined;
 
   constructor(
     @IRenderService private readonly _renderService: IRenderService,
@@ -63,9 +68,20 @@ export class MouseService implements IMouseService {
       mousedrag: (ev: Event) => this._handleMouseDrag(ctx, ev as MouseEvent),
       mousemove: (ev: Event) => this._handleMouseMove(ctx, ev as MouseEvent)
     };
+    this._altMouseCursor = new AltMouseCursorController(
+      element,
+      document,
+      () => this._mouseStateService.areMouseEventsActive
+        && !!this._optionsService.rawOptions.mouseEventsRequireAlt
+    );
+    register(this._altMouseCursor);
     register(this._mouseStateService.onProtocolChange(events => {
       this._handleProtocolChange(ctx, eventListeners, events);
     }));
+    register(this._optionsService.onSpecificOptionChange('mouseEventsRequireAlt', () => {
+      this._syncMouseModeState(element);
+      this._altMouseCursor?.sync();
+    }));
     // force initial onProtocolChange so we dont miss early mouse requests
     this._mouseStateService.activeProtocol = this._mouseStateService.activeProtocol;
 
@@ -153,6 +169,19 @@ export class MouseService implements IMouseService {
       return false;
     }
 
+    if (but !== CoreMouseButton.WHEEL
+      && this._optionsService.rawOptions.mouseEventsRequireAlt
+      && this._mouseStateService.areMouseEventsActive
+      && !ev.altKey) {
+      return false;
+    }
+
+    // Alt is only used locally to gate mouse passthrough; do not forward it to the
+    // application (e.g. tmux ignores alt-modified mouse reports).
+    const stripAltFromReport = but !== CoreMouseButton.WHEEL
+      && this._optionsService.rawOptions.mouseEventsRequireAlt
+      && this._mouseStateService.areMouseEventsActive;
+
     return this._triggerMouseEvent({
       col: pos.col,
       row: pos.row,
@@ -161,7 +190,7 @@ export class MouseService implements IMouseService {
       button: but,
       action,
       ctrl: ev.ctrlKey,
-      alt: ev.altKey,
+      alt: stripAltFromReport ? false : ev.altKey,
       shift: ev.shiftKey
     });
   }
@@ -353,6 +382,21 @@ export class MouseService implements IMouseService {
     this._touchScrollAccumulator = 0;
   }
 
+  private _syncMouseModeState(element: HTMLElement): void {
+    if (this._mouseStateService.areMouseEventsActive) {
+      if (this._optionsService.rawOptions.mouseEventsRequireAlt) {
+        this._altMouseCursor?.resetClass();
+        this._selectionService.enable();
+      } else {
+        element.classList.add(MouseEventCssClasses.ENABLE_MOUSE_EVENTS);
+        this._selectionService.disable();
+      }
+    } else {
+      element.classList.remove(MouseEventCssClasses.ENABLE_MOUSE_EVENTS);
+      this._selectionService.enable();
+    }
+  }
+
   private _handleProtocolChange(ctx: IMouseBindContext, eventListeners: Record<'mouseup' | 'wheel' | 'mousedrag' | 'mousemove', EventListener>, events: CoreMouseEventType): void {
     const { element, document } = ctx.target;
     const { requestedEvents } = ctx;
@@ -361,13 +405,11 @@ export class MouseService implements IMouseService {
       if (this._optionsService.rawOptions.logLevel === 'debug') {
         this._logService.debug('Binding to mouse events:', this._explainEvents(events));
       }
-      element.classList.add('enable-mouse-events');
-      this._selectionService.disable();
     } else {
       this._logService.debug('Unbinding from mouse events.');
-      element.classList.remove('enable-mouse-events');
-      this._selectionService.enable();
     }
+    this._syncMouseModeState(element);
+    this._altMouseCursor?.sync();
 
     // add/remove handlers from requestedEvents
     if (!(events & CoreMouseEventType.MOVE)) {
@@ -537,3 +579,64 @@ export class MouseService implements IMouseService {
   }
 
 }
+
+/**
+ * Toggles MouseEventCssClasses.ENABLE_MOUSE_EVENTS on the terminal element while alt is held when
+ * `mouseEventsRequireAlt` is active. DOM listeners are only registered while active.
+ */
+export class AltMouseCursorController implements IDisposable {
+  private readonly _listeners = new MutableDisposable<IDisposable>();
+
+  constructor(
+    private readonly _element: HTMLElement,
+    private readonly _document: Document,
+    private readonly _isActive: () => boolean
+  ) {
+  }
+
+  public dispose(): void {
+    this._listeners.dispose();
+  }
+
+  public sync(): void {
+    this._listeners.clear();
+
+    if (!this._isActive()) {
+      return;
+    }
+
+    const store = new DisposableStore();
+    const syncFromModifier = (ev: KeyboardEvent | MouseEvent): void => this.syncFromModifier(ev);
+    store.add(addDisposableListener(this._document, 'keydown', syncFromModifier));
+    store.add(addDisposableListener(this._document, 'keyup', syncFromModifier));
+    store.add(addDisposableListener(this._element, 'mousemove', syncFromModifier));
+    const targetWindow = this._element.ownerDocument?.defaultView;
+    if (targetWindow) {
+      store.add(addDisposableListener(targetWindow, 'blur', () => {
+        if (this._isActive()) {
+          this.resetClass();
+        }
+      }));
+    }
+    this._listeners.value = store;
+  }
+
+  public resetClass(): void {
+    this._updateClass(false);
+  }
+
+  public syncFromModifier(ev: KeyboardEvent | MouseEvent): void {
+    if (!this._isActive()) {
+      return;
+    }
+    this._updateClass(ev.getModifierState('Alt'));
+  }
+
+  private _updateClass(altHeld: boolean): void {
+    if (altHeld) {
+      this._element.classList.add(MouseEventCssClasses.ENABLE_MOUSE_EVENTS);
+    } else {
+      this._element.classList.remove(MouseEventCssClasses.ENABLE_MOUSE_EVENTS);
+    }
+  }
+}

src/browser/services/SelectionService.test.ts

@@ -7,7 +7,7 @@ import { assert } from 'chai';
 import { SelectionService, SelectionMode } from './SelectionService';
 import { SelectionModel } from 'browser/selection/SelectionModel';
 import { IBufferLine } from 'common/Types';
-import { MockBufferService, MockOptionsService, MockCoreService, createCellData } from 'common/TestUtils.test';
+import { MockBufferService, MockOptionsService, MockCoreService, MockMouseStateService, createCellData } from 'common/TestUtils.test';
 import { BufferLine } from 'common/buffer/BufferLine';
 import { BufferLineStringCache } from 'common/buffer/BufferLineStringCache';
 import { IBufferService, IOptionsService } from 'common/services/Services';
@@ -22,9 +22,10 @@ class TestSelectionService extends SelectionService {
   constructor(
     bufferService: IBufferService,
     optionsService: IOptionsService,
-    renderService: IRenderService
+    renderService: IRenderService,
+    public readonly mouseStateService: MockMouseStateService
   ) {
-    super(null!, null!, null!, bufferService, new MockCoreService(), new MockMouseService(), optionsService, renderService, new MockCoreBrowserService());
+    super(null!, null!, null!, bufferService, new MockCoreService(), new MockMouseService(), optionsService, mouseStateService, renderService, new MockCoreBrowserService());
   }
 
   public get model(): SelectionModel { return this._model; }
@@ -45,16 +46,18 @@ describe('SelectionService', () => {
   let buffer: IBuffer;
   let bufferService: IBufferService;
   let optionsService: IOptionsService;
+  let mouseStateService: MockMouseStateService;
   let selectionService: TestSelectionService;
 
   beforeEach(() => {
     optionsService = new MockOptionsService();
+    mouseStateService = new MockMouseStateService();
     bufferService = new MockBufferService(20, 20, optionsService);
     buffer = bufferService.buffer;
     const renderService = new MockRenderService();
     renderService.dimensions.css.canvas.height = 10 * 20;
     renderService.dimensions.css.canvas.width = 10 * 20;
-    selectionService = new TestSelectionService(bufferService, optionsService, renderService);
+    selectionService = new TestSelectionService(bufferService, optionsService, renderService, mouseStateService);
   });
 
   function stringToRow(text: string): IBufferLine {
@@ -499,5 +502,21 @@ describe('SelectionService', () => {
       assert.isFalse(selectionService.areCoordsInSelection([2, 1], [2, 0], [2, 1]));
     });
   });
+
+  describe('shouldForceSelection', () => {
+    it('should force selection without alt when mouseEventsRequireAlt is enabled', () => {
+      optionsService.options.mouseEventsRequireAlt = true;
+      mouseStateService.areMouseEventsActive = true;
+      assert.isTrue(selectionService.shouldForceSelection({ altKey: false } as MouseEvent));
+      assert.isFalse(selectionService.shouldForceSelection({ altKey: true } as MouseEvent));
+    });
+
+    it('should take precedence over macOptionClickForcesSelection', () => {
+      optionsService.options.mouseEventsRequireAlt = true;
+      optionsService.options.macOptionClickForcesSelection = true;
+      mouseStateService.areMouseEventsActive = true;
+      assert.isFalse(selectionService.shouldForceSelection({ altKey: true } as MouseEvent));
+    });
+  });
 });
 

src/browser/services/SelectionService.ts

@@ -15,7 +15,7 @@ import { IBufferLine, ICellData, IDisposable } from 'common/Types';
 import { getRangeLength } from 'common/buffer/BufferRange';
 import { CellData } from 'common/buffer/CellData';
 import { IBuffer } from 'common/buffer/Types';
-import { IBufferService, ICoreService, IOptionsService } from 'common/services/Services';
+import { IBufferService, ICoreService, IMouseStateService, IOptionsService } from 'common/services/Services';
 import { Emitter } from 'common/Event';
 
 const enum Constants {
@@ -127,6 +127,7 @@ export class SelectionService extends Disposable implements ISelectionService {
     @ICoreService private readonly _coreService: ICoreService,
     @IMouseCoordsService private readonly _mouseCoordsService: IMouseCoordsService,
     @IOptionsService private readonly _optionsService: IOptionsService,
+    @IMouseStateService private readonly _mouseStateService: IMouseStateService,
     @IRenderService private readonly _renderService: IRenderService,
     @ICoreBrowserService private readonly _coreBrowserService: ICoreBrowserService
   ) {
@@ -434,6 +435,10 @@ export class SelectionService extends Disposable implements ISelectionService {
    * @param event The mouse event.
    */
   public shouldForceSelection(event: MouseEvent): boolean {
+    if (this._optionsService.rawOptions.mouseEventsRequireAlt && this._mouseStateService.areMouseEventsActive) {
+      return !event.altKey;
+    }
+
     if (Browser.isMac) {
       return event.altKey && this._optionsService.rawOptions.macOptionClickForcesSelection;
     }
@@ -458,6 +463,10 @@ export class SelectionService extends Disposable implements ISelectionService {
       return;
     }
 
+    if (this._optionsService.rawOptions.mouseEventsRequireAlt && this._mouseStateService.areMouseEventsActive && event.altKey) {
+      return;
+    }
+
     // Allow selection when using a specific modifier key, even when disabled
     if (!this._enabled) {
       if (!this.shouldForceSelection(event)) {
@@ -596,6 +605,9 @@ export class SelectionService extends Disposable implements ISelectionService {
    * @param event the mouse or keyboard event
    */
   public shouldColumnSelect(event: KeyboardEvent | MouseEvent): boolean {
+    if (this._optionsService.rawOptions.mouseEventsRequireAlt && this._mouseStateService.areMouseEventsActive) {
+      return false;
+    }
     return event.altKey && !(Browser.isMac && this._optionsService.rawOptions.macOptionClickForcesSelection);
   }
 
@@ -918,10 +930,10 @@ export class SelectionService extends Disposable implements ISelectionService {
     // Calculate the start _column_, converting the the string indexes back to
     // column coordinates.
     let start =
-        startIndex // The index of the selection's start char in the line string
+      startIndex // The index of the selection's start char in the line string
-        + charOffset // The difference between the initial char's column and index
+      + charOffset // The difference between the initial char's column and index
-        - leftWideCharCount // The number of wide chars left of the initial char
+      - leftWideCharCount // The number of wide chars left of the initial char
-        + leftLongCharOffset; // The number of additional chars left of the initial char added by columns with strings longer than 1 (emojis)
+      + leftLongCharOffset; // The number of additional chars left of the initial char added by columns with strings longer than 1 (emojis)
 
     // Calculate the length in _columns_, converting the the string indexes back
     // to column coordinates.

src/common/TaskQueue.ts

@@ -74,10 +74,10 @@ abstract class TaskQueue implements ITaskQueue {
 
   private _process(deadline: ITaskDeadline): void {
     this._idleCallback = undefined;
-    let taskDuration = 0;
+    let taskDuration: number;
     let longestTask = 0;
     let lastDeadlineRemaining = deadline.timeRemaining();
-    let deadlineRemaining = 0;
+    let deadlineRemaining: number;
     while (this._i < this._tasks.length) {
       taskDuration = performance.now();
       if (!this._tasks[this._i]()) {

src/common/data/Charsets.ts

@@ -98,8 +98,7 @@ CHARSETS['4'] = {
  * ESC (C or ESC (5
  * Reference: http://vt100.net/docs/vt220-rm/table2-7.html
  */
-CHARSETS['C'] =
+CHARSETS['C'] = CHARSETS['5'] = {
-CHARSETS['5'] = {
   '[': 'Ä',
   '\\': 'Ö',
   ']': 'Å',
@@ -185,8 +184,7 @@ CHARSETS['Y'] = {
  * ESC (E or ESC (6
  * Reference: http://vt100.net/docs/vt220-rm/table2-12.html
  */
-CHARSETS['E'] =
+CHARSETS['E'] = CHARSETS['6'] = {
-CHARSETS['6'] = {
   '@': 'Ä',
   '[': 'Æ',
   '\\': 'Ø',
@@ -220,8 +218,7 @@ CHARSETS['Z'] = {
  * ESC (H or ESC (7
  * Reference: http://vt100.net/docs/vt220-rm/table2-14.html
  */
-CHARSETS['H'] =
+CHARSETS['H'] = CHARSETS['7'] = {
-CHARSETS['7'] = {
   '@': 'É',
   '[': 'Ä',
   '\\': 'Ö',

src/common/input/TextDecoder.ts

@@ -148,7 +148,7 @@ export class Utf8ToUtf32 {
     let byte2: number;
     let byte3: number;
     let byte4: number;
-    let codepoint = 0;
+    let codepoint;
     let startPos = 0;
 
     // handle leftover bytes

src/common/parser/EscapeSequenceParser.ts

@@ -572,8 +572,8 @@ export class EscapeSequenceParser extends Disposable implements IEscapeSequenceP
    * ```
    */
   public parse(data: Uint32Array, length: number, promiseResult?: boolean): void | Promise<boolean> {
-    let code = 0;
+    let code: number;
-    let transition = 0;
+    let transition: number;
     let start = 0;
     let handlerResult: void | boolean | Promise<boolean>;
 

src/common/services/DecorationService.ts

@@ -88,12 +88,10 @@ export class DecorationService extends Disposable implements IDecorationService
     if (!bucket) {
       return;
     }
-    let xmin = 0;
-    let xmax = 0;
     for (const d of bucket) {
-      xmin = d.options.x ?? 0;
+      $xmin = d.options.x ?? 0;
-      xmax = xmin + (d.options.width ?? 1);
+      $xmax = $xmin + (d.options.width ?? 1);
-      if (x >= xmin && x < xmax && (!layer || (d.options.layer ?? 'bottom') === layer)) {
+      if (x >= $xmin && x < $xmax && (!layer || (d.options.layer ?? 'bottom') === layer)) {
         yield d;
       }
     }

src/common/services/OptionsService.ts

@@ -41,6 +41,7 @@ export const DEFAULT_OPTIONS: Readonly<Required<ITerminalOptions>> = {
   macOptionIsMeta: false,
   macOptionClickForcesSelection: false,
   minimumContrastRatio: 1,
+  mouseEventsRequireAlt: false,
   disableStdin: false,
   allowProposedApi: false,
   allowTransparency: false,

src/common/services/Services.ts

@@ -234,6 +234,7 @@ export interface ITerminalOptions {
   macOptionIsMeta?: boolean;
   macOptionClickForcesSelection?: boolean;
   minimumContrastRatio?: number;
+  mouseEventsRequireAlt?: boolean;
   reflowCursorLine?: boolean;
   rescaleOverlappingGlyphs?: boolean;
   rightClickSelectsWord?: boolean;

src/tsconfig-library-base.json

@@ -4,7 +4,6 @@
     "composite": true,
     "strict": true,
     "declarationMap": true,
-    "experimentalDecorators": true,
+    "experimentalDecorators": true
-    "downlevelIteration": true
   }
 }

test/benchmark/tsconfig.json

@@ -8,10 +8,10 @@
     "types": [
       "../../node_modules/@types/node"
     ],
-    "moduleResolution": "node",
+    "moduleResolution": "nodenext",
     "strict": false,
     "target": "es2021",
-    "module": "commonjs",
+    "module": "nodenext",
     "paths": {
       "common/*": [ "../../src/common/*" ],
       "browser/*": [ "../../src/browser/*" ],