Make terminal rendering work in popout windows

Add support for the parent element (what is passed to Terminal.open)
being in a different (same origin) window. Accesses to DOM APIs such
as requestAnimationFrame and devicePixelRatio thus need to be scoped
to the corrent window, instead of assuming that it's the same as the
window/global scope where the code is running.

This is done by inferring a parent window at the creation time, and
then storing it in CoreBrowserService, which is already passed to most
places that need it.

To catch future regressions, an ESLint rule that checks for global
accesses is added (it uses AST selectors via the no-restricted-syntax
rule).

This should also be applicable when the parent element is an iframe.

Fixes #3758

.eslintrc.json

@@ -147,6 +147,29 @@
         ]
       }
     ],
+    "no-restricted-syntax": [
+      "warn",
+      {
+        "selector": "CallExpression[callee.name='requestAnimationFrame']",
+        "message": "The global requestAnimationFrame() should be avoided, call it on the parent window from ICoreBrowserService."
+      },
+      {
+        "selector": "CallExpression[callee.name='cancelAnimationFrame']",
+        "message": "The global cancelAnimationFrame() should be avoided, call it on the parent window from ICoreBrowserService."
+      },
+      {
+        "selector": "CallExpression > MemberExpression[object.name='window'][property.name='requestAnimationFrame']",
+        "message": "window.requestAnimationFrame() should be avoided, call it on the parent window from ICoreBrowserService."
+      },
+      {
+        "selector": "CallExpression > MemberExpression[object.name='window'][property.name='cancelAnimationFrame']",
+        "message": "window.cancelAnimationFrame() should be avoided, call it on the parent window from ICoreBrowserService."
+      },
+      {
+        "selector": "MemberExpression[object.name='window'][property.name='devicePixelRatio']",
+        "message": "window.devicePixelRatio should be avoided, get it from ICoreBrowserService."
+      }
+    ],
     "no-trailing-spaces": "warn",
     "no-unsafe-finally": "warn",
     "no-var": "warn",

addons/xterm-addon-canvas/src/BaseRenderLayer.ts

@@ -15,6 +15,7 @@ import { AttributeData } from 'common/buffer/AttributeData';
 import { IColorSet } from 'browser/Types';
 import { CellData } from 'common/buffer/CellData';
 import { IBufferService, IDecorationService, IOptionsService } from 'common/services/Services';
+import { ICoreBrowserService } from 'browser/services/Services';
 import { excludeFromContrastRatioDemands, throwIfFalsy } from 'browser/renderer/RendererUtils';
 import { channels, color, rgba } from 'common/Color';
 import { removeElementFromParent } from 'browser/Dom';
@@ -60,7 +61,8 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     private _rendererId: number,
     protected readonly _bufferService: IBufferService,
     protected readonly _optionsService: IOptionsService,
-    protected readonly _decorationService: IDecorationService
+    protected readonly _decorationService: IDecorationService,
+    protected readonly _coreBrowserService: ICoreBrowserService
   ) {
     this._canvas = document.createElement('canvas');
     this._canvas.classList.add(`xterm-${id}-layer`);
@@ -125,7 +127,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     if (this._scaledCharWidth <= 0 && this._scaledCharHeight <= 0) {
       return;
     }
-    this._charAtlas = acquireCharAtlas(this._optionsService.rawOptions, this._rendererId, colorSet, this._scaledCharWidth, this._scaledCharHeight);
+    this._charAtlas = acquireCharAtlas(this._optionsService.rawOptions, this._rendererId, colorSet, this._scaledCharWidth, this._scaledCharHeight, this._coreBrowserService.dpr);
     this._charAtlas.warmUp();
   }
 
@@ -180,9 +182,9 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     const cellOffset = Math.ceil(this._scaledCellHeight * 0.5);
     this._ctx.fillRect(
       x * this._scaledCellWidth,
-      (y + 1) * this._scaledCellHeight - cellOffset - window.devicePixelRatio,
+      (y + 1) * this._scaledCellHeight - cellOffset - this._coreBrowserService.dpr,
       width * this._scaledCellWidth,
-      window.devicePixelRatio);
+      this._coreBrowserService.dpr);
   }
 
   /**
@@ -194,23 +196,24 @@ export abstract class BaseRenderLayer implements IRenderLayer {
   protected _fillBottomLineAtCells(x: number, y: number, width: number = 1, pixelOffset: number = 0): void {
     this._ctx.fillRect(
       x * this._scaledCellWidth,
-      (y + 1) * this._scaledCellHeight + pixelOffset - window.devicePixelRatio - 1 /* Ensure it's drawn within the cell */,
+      (y + 1) * this._scaledCellHeight + pixelOffset - this._coreBrowserService.dpr - 1 /* Ensure it's drawn within the cell */,
       width * this._scaledCellWidth,
-      window.devicePixelRatio);
+      this._coreBrowserService.dpr);
   }
 
   protected _curlyUnderlineAtCell(x: number, y: number, width: number = 1): void {
     this._ctx.save();
     this._ctx.beginPath();
     this._ctx.strokeStyle = this._ctx.fillStyle;
-    this._ctx.lineWidth = window.devicePixelRatio;
+    const lineWidth = this._coreBrowserService.dpr;
+    this._ctx.lineWidth = lineWidth;
     for (let xOffset = 0; xOffset < width; xOffset++) {
       const xLeft = (x + xOffset) * this._scaledCellWidth;
       const xMid = (x + xOffset + 0.5) * this._scaledCellWidth;
       const xRight = (x + xOffset + 1) * this._scaledCellWidth;
-      const yMid = (y + 1) * this._scaledCellHeight - window.devicePixelRatio - 1;
-      const yMidBot = yMid - window.devicePixelRatio;
-      const yMidTop = yMid + window.devicePixelRatio;
+      const yMid = (y + 1) * this._scaledCellHeight - lineWidth - 1;
+      const yMidBot = yMid - lineWidth;
+      const yMidTop = yMid + lineWidth;
       this._ctx.moveTo(xLeft, yMid);
       this._ctx.bezierCurveTo(
         xLeft, yMidBot,
@@ -231,10 +234,11 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     this._ctx.save();
     this._ctx.beginPath();
     this._ctx.strokeStyle = this._ctx.fillStyle;
-    this._ctx.lineWidth = window.devicePixelRatio;
-    this._ctx.setLineDash([window.devicePixelRatio * 2, window.devicePixelRatio]);
+    const lineWidth = this._coreBrowserService.dpr;
+    this._ctx.lineWidth = lineWidth;
+    this._ctx.setLineDash([lineWidth * 2, lineWidth]);
     const xLeft = x * this._scaledCellWidth;
-    const yMid = (y + 1) * this._scaledCellHeight - window.devicePixelRatio - 1;
+    const yMid = (y + 1) * this._scaledCellHeight - lineWidth - 1;
     this._ctx.moveTo(xLeft, yMid);
     for (let xOffset = 0; xOffset < width; xOffset++) {
       // const xLeft = x * this._scaledCellWidth;
@@ -250,11 +254,12 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     this._ctx.save();
     this._ctx.beginPath();
     this._ctx.strokeStyle = this._ctx.fillStyle;
-    this._ctx.lineWidth = window.devicePixelRatio;
-    this._ctx.setLineDash([window.devicePixelRatio * 4, window.devicePixelRatio * 3]);
+    const lineWidth = this._coreBrowserService.dpr;
+    this._ctx.lineWidth = lineWidth;
+    this._ctx.setLineDash([lineWidth * 4, lineWidth * 3]);
     const xLeft = x * this._scaledCellWidth;
     const xRight = (x + width) * this._scaledCellWidth;
-    const yMid = (y + 1) * this._scaledCellHeight - window.devicePixelRatio - 1;
+    const yMid = (y + 1) * this._scaledCellHeight - lineWidth - 1;
     this._ctx.moveTo(xLeft, yMid);
     this._ctx.lineTo(xRight, yMid);
     this._ctx.stroke();
@@ -272,7 +277,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     this._ctx.fillRect(
       x * this._scaledCellWidth,
       y * this._scaledCellHeight,
-      window.devicePixelRatio * width,
+      this._coreBrowserService.dpr * width,
       this._scaledCellHeight);
   }
 
@@ -283,12 +288,13 @@ export abstract class BaseRenderLayer implements IRenderLayer {
    * @param y The row to fill.
    */
   protected _strokeRectAtCell(x: number, y: number, width: number, height: number): void {
-    this._ctx.lineWidth = window.devicePixelRatio;
+    const lineWidth = this._coreBrowserService.dpr;
+    this._ctx.lineWidth = lineWidth;
     this._ctx.strokeRect(
-      x * this._scaledCellWidth + window.devicePixelRatio / 2,
-      y * this._scaledCellHeight + (window.devicePixelRatio / 2),
-      width * this._scaledCellWidth - window.devicePixelRatio,
-      (height * this._scaledCellHeight) - window.devicePixelRatio);
+      x * this._scaledCellWidth + lineWidth / 2,
+      y * this._scaledCellHeight + (lineWidth / 2),
+      width * this._scaledCellWidth - lineWidth,
+      (height * this._scaledCellHeight) - lineWidth);
   }
 
   /**
@@ -344,7 +350,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     // Draw custom characters if applicable
     let drawSuccess = false;
     if (this._optionsService.rawOptions.customGlyphs !== false) {
-      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x * this._scaledCellWidth, y * this._scaledCellHeight, this._scaledCellWidth, this._scaledCellHeight, this._optionsService.rawOptions.fontSize);
+      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x * this._scaledCellWidth, y * this._scaledCellHeight, this._scaledCellWidth, this._scaledCellHeight, this._optionsService.rawOptions.fontSize, this._coreBrowserService.dpr);
     }
 
     // Draw the character
@@ -472,7 +478,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     // Draw custom characters if applicable
     let drawSuccess = false;
     if (this._optionsService.rawOptions.customGlyphs !== false) {
-      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x * this._scaledCellWidth, y * this._scaledCellHeight, this._scaledCellWidth, this._scaledCellHeight, this._optionsService.rawOptions.fontSize);
+      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x * this._scaledCellWidth, y * this._scaledCellHeight, this._scaledCellWidth, this._scaledCellHeight, this._optionsService.rawOptions.fontSize, this._coreBrowserService.dpr);
     }
 
     // Draw the character
@@ -509,7 +515,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     const fontWeight = isBold ? this._optionsService.rawOptions.fontWeightBold : this._optionsService.rawOptions.fontWeight;
     const fontStyle = isItalic ? 'italic' : '';
 
-    return `${fontStyle} ${fontWeight} ${this._optionsService.rawOptions.fontSize * window.devicePixelRatio}px ${this._optionsService.rawOptions.fontFamily}`;
+    return `${fontStyle} ${fontWeight} ${this._optionsService.rawOptions.fontSize * this._coreBrowserService.dpr}px ${this._optionsService.rawOptions.fontFamily}`;
   }
 
   private _getContrastColor(cell: CellData, x: number, y: number): IColor | undefined {

addons/xterm-addon-canvas/src/CanvasRenderer.ts

@@ -39,16 +39,16 @@ export class CanvasRenderer extends Disposable implements IRenderer {
     private readonly _optionsService: IOptionsService,
     characterJoinerService: ICharacterJoinerService,
     coreService: ICoreService,
-    coreBrowserService: ICoreBrowserService,
+    private readonly _coreBrowserService: ICoreBrowserService,
     decorationService: IDecorationService
   ) {
     super();
     const allowTransparency = this._optionsService.rawOptions.allowTransparency;
     this._renderLayers = [
-      new TextRenderLayer(this._screenElement, 0, this._colors, allowTransparency, this._id, this._bufferService, this._optionsService, characterJoinerService, decorationService),
-      new SelectionRenderLayer(this._screenElement, 1, this._colors, this._id, this._bufferService, coreBrowserService, decorationService, this._optionsService),
-      new LinkRenderLayer(this._screenElement, 2, this._colors, this._id, linkifier2, this._bufferService, this._optionsService, decorationService),
-      new CursorRenderLayer(this._screenElement, 3, this._colors, this._id, this._onRequestRedraw, this._bufferService, this._optionsService, coreService, coreBrowserService, decorationService)
+      new TextRenderLayer(this._screenElement, 0, this._colors, allowTransparency, this._id, this._bufferService, this._optionsService, characterJoinerService, decorationService, this._coreBrowserService),
+      new SelectionRenderLayer(this._screenElement, 1, this._colors, this._id, this._bufferService, this._coreBrowserService, decorationService, this._optionsService),
+      new LinkRenderLayer(this._screenElement, 2, this._colors, this._id, linkifier2, this._bufferService, this._optionsService, decorationService, this._coreBrowserService),
+      new CursorRenderLayer(this._screenElement, 3, this._colors, this._id, this._onRequestRedraw, this._bufferService, this._optionsService, coreService, this._coreBrowserService, decorationService)
     ];
     this.dimensions = {
       scaledCharWidth: 0,
@@ -64,10 +64,10 @@ export class CanvasRenderer extends Disposable implements IRenderer {
       actualCellWidth: 0,
       actualCellHeight: 0
     };
-    this._devicePixelRatio = window.devicePixelRatio;
+    this._devicePixelRatio = this._coreBrowserService.dpr;
     this._updateDimensions();
 
-    this.register(observeDevicePixelDimensions(this._renderLayers[0].canvas, (w, h) => this._setCanvasDevicePixelDimensions(w, h)));
+    this.register(observeDevicePixelDimensions(this._renderLayers[0].canvas, this._coreBrowserService.window, (w, h) => this._setCanvasDevicePixelDimensions(w, h)));
 
     this.onOptionsChanged();
   }
@@ -83,8 +83,8 @@ export class CanvasRenderer extends Disposable implements IRenderer {
   public onDevicePixelRatioChange(): void {
     // If the device pixel ratio changed, the char atlas needs to be regenerated
     // and the terminal needs to refreshed
-    if (this._devicePixelRatio !== window.devicePixelRatio) {
-      this._devicePixelRatio = window.devicePixelRatio;
+    if (this._devicePixelRatio !== this._coreBrowserService.dpr) {
+      this._devicePixelRatio = this._coreBrowserService.dpr;
       this.onResize(this._bufferService.cols, this._bufferService.rows);
     }
   }
@@ -175,16 +175,17 @@ export class CanvasRenderer extends Disposable implements IRenderer {
     }
 
     // See the WebGL renderer for an explanation of this section.
-    this.dimensions.scaledCharWidth = Math.floor(this._charSizeService.width * window.devicePixelRatio);
-    this.dimensions.scaledCharHeight = Math.ceil(this._charSizeService.height * window.devicePixelRatio);
+    const dpr = this._coreBrowserService.dpr;
+    this.dimensions.scaledCharWidth = Math.floor(this._charSizeService.width * dpr);
+    this.dimensions.scaledCharHeight = Math.ceil(this._charSizeService.height * dpr);
     this.dimensions.scaledCellHeight = Math.floor(this.dimensions.scaledCharHeight * this._optionsService.rawOptions.lineHeight);
     this.dimensions.scaledCharTop = this._optionsService.rawOptions.lineHeight === 1 ? 0 : Math.round((this.dimensions.scaledCellHeight - this.dimensions.scaledCharHeight) / 2);
     this.dimensions.scaledCellWidth = this.dimensions.scaledCharWidth + Math.round(this._optionsService.rawOptions.letterSpacing);
     this.dimensions.scaledCharLeft = Math.floor(this._optionsService.rawOptions.letterSpacing / 2);
     this.dimensions.scaledCanvasHeight = this._bufferService.rows * this.dimensions.scaledCellHeight;
     this.dimensions.scaledCanvasWidth = this._bufferService.cols * this.dimensions.scaledCellWidth;
-    this.dimensions.canvasHeight = Math.round(this.dimensions.scaledCanvasHeight / window.devicePixelRatio);
-    this.dimensions.canvasWidth = Math.round(this.dimensions.scaledCanvasWidth / window.devicePixelRatio);
+    this.dimensions.canvasHeight = Math.round(this.dimensions.scaledCanvasHeight / dpr);
+    this.dimensions.canvasWidth = Math.round(this.dimensions.scaledCanvasWidth / dpr);
     this.dimensions.actualCellHeight = this.dimensions.canvasHeight / this._bufferService.rows;
     this.dimensions.actualCellWidth = this.dimensions.canvasWidth / this._bufferService.cols;
   }

addons/xterm-addon-canvas/src/CursorRenderLayer.ts

@@ -40,10 +40,10 @@ export class CursorRenderLayer extends BaseRenderLayer {
     bufferService: IBufferService,
     optionsService: IOptionsService,
     private readonly _coreService: ICoreService,
-    private readonly _coreBrowserService: ICoreBrowserService,
+    coreBrowserService: ICoreBrowserService,
     decorationService: IDecorationService
   ) {
-    super(container, 'cursor', zIndex, true, colors, rendererId, bufferService, optionsService, decorationService);
+    super(container, 'cursor', zIndex, true, colors, rendererId, bufferService, optionsService, decorationService, coreBrowserService);
     this._state = {
       x: 0,
       y: 0,
@@ -99,7 +99,7 @@ export class CursorRenderLayer extends BaseRenderLayer {
       if (!this._cursorBlinkStateManager) {
         this._cursorBlinkStateManager = new CursorBlinkStateManager(this._coreBrowserService.isFocused, () => {
           this._render(true);
-        });
+        }, this._coreBrowserService);
       }
     } else {
       this._cursorBlinkStateManager?.dispose();
@@ -196,7 +196,7 @@ export class CursorRenderLayer extends BaseRenderLayer {
   private _clearCursor(): void {
     if (this._state) {
       // Avoid potential rounding errors when device pixel ratio is less than 1
-      if (window.devicePixelRatio < 1) {
+      if (this._coreBrowserService.dpr < 1) {
         this._clearAll();
       } else {
         this._clearCells(this._state.x, this._state.y, this._state.width, 1);
@@ -258,7 +258,8 @@ class CursorBlinkStateManager {
 
   constructor(
     isFocused: boolean,
-    private _renderCallback: () => void
+    private _renderCallback: () => void,
+    private _coreBrowserService: ICoreBrowserService
   ) {
     this.isCursorVisible = true;
     if (isFocused) {
@@ -270,15 +271,15 @@ class CursorBlinkStateManager {
 
   public dispose(): void {
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
     if (this._blinkStartTimeout) {
-      window.clearTimeout(this._blinkStartTimeout);
+      this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
       this._blinkStartTimeout = undefined;
     }
     if (this._animationFrame) {
-      window.cancelAnimationFrame(this._animationFrame);
+      this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
   }
@@ -292,7 +293,7 @@ class CursorBlinkStateManager {
     // Force a cursor render to ensure it's visible and in the correct position
     this.isCursorVisible = true;
     if (!this._animationFrame) {
-      this._animationFrame = window.requestAnimationFrame(() => {
+      this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
         this._renderCallback();
         this._animationFrame = undefined;
       });
@@ -302,7 +303,7 @@ class CursorBlinkStateManager {
   private _restartInterval(timeToStart: number = BLINK_INTERVAL): void {
     // Clear any existing interval
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
 
@@ -310,7 +311,7 @@ class CursorBlinkStateManager {
     // the regular interval is setup in order to support restarting the blink
     // animation in a lightweight way (without thrashing clearInterval and
     // setInterval).
-    this._blinkStartTimeout = window.setTimeout(() => {
+    this._blinkStartTimeout = this._coreBrowserService.window.setTimeout(() => {
       // Check if another animation restart was requested while this was being
       // started
       if (this._animationTimeRestarted) {
@@ -324,13 +325,13 @@ class CursorBlinkStateManager {
 
       // Hide the cursor
       this.isCursorVisible = false;
-      this._animationFrame = window.requestAnimationFrame(() => {
+      this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
         this._renderCallback();
         this._animationFrame = undefined;
       });
 
       // Setup the blink interval
-      this._blinkInterval = window.setInterval(() => {
+      this._blinkInterval = this._coreBrowserService.window.setInterval(() => {
         // Adjust the animation time if it was restarted
         if (this._animationTimeRestarted) {
           // calc time diff
@@ -343,7 +344,7 @@ class CursorBlinkStateManager {
 
         // Invert visibility and render
         this.isCursorVisible = !this.isCursorVisible;
-        this._animationFrame = window.requestAnimationFrame(() => {
+        this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
           this._renderCallback();
           this._animationFrame = undefined;
         });
@@ -354,15 +355,15 @@ class CursorBlinkStateManager {
   public pause(): void {
     this.isCursorVisible = true;
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
     if (this._blinkStartTimeout) {
-      window.clearTimeout(this._blinkStartTimeout);
+      this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
       this._blinkStartTimeout = undefined;
     }
     if (this._animationFrame) {
-      window.cancelAnimationFrame(this._animationFrame);
+      this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
   }

addons/xterm-addon-canvas/src/LinkRenderLayer.ts

@@ -6,6 +6,7 @@
 import { IRenderDimensions } from 'browser/renderer/Types';
 import { BaseRenderLayer } from './BaseRenderLayer';
 import { INVERTED_DEFAULT_COLOR } from 'browser/renderer/Constants';
+import { ICoreBrowserService } from 'browser/services/Services';
 import { is256Color } from './atlas/CharAtlasUtils';
 import { IColorSet, ILinkifierEvent, ILinkifier2 } from 'browser/Types';
 import { IBufferService, IDecorationService, IOptionsService } from 'common/services/Services';
@@ -21,9 +22,10 @@ export class LinkRenderLayer extends BaseRenderLayer {
     linkifier2: ILinkifier2,
     bufferService: IBufferService,
     optionsService: IOptionsService,
-    decorationService: IDecorationService
+    decorationService: IDecorationService,
+    coreBrowserService: ICoreBrowserService
   ) {
-    super(container, 'link', zIndex, true, colors, rendererId, bufferService, optionsService, decorationService);
+    super(container, 'link', zIndex, true, colors, rendererId, bufferService, optionsService, decorationService, coreBrowserService);
 
     linkifier2.onShowLinkUnderline(e => this._onShowLinkUnderline(e));
     linkifier2.onHideLinkUnderline(e => this._onHideLinkUnderline(e));

addons/xterm-addon-canvas/src/SelectionRenderLayer.ts

@@ -25,11 +25,11 @@ export class SelectionRenderLayer extends BaseRenderLayer {
     colors: IColorSet,
     rendererId: number,
     bufferService: IBufferService,
-    private readonly _coreBrowserService: ICoreBrowserService,
+    coreBrowserService: ICoreBrowserService,
     decorationService: IDecorationService,
     optionsService: IOptionsService
   ) {
-    super(container, 'selection', zIndex, true, colors, rendererId, bufferService, optionsService, decorationService);
+    super(container, 'selection', zIndex, true, colors, rendererId, bufferService, optionsService, decorationService, coreBrowserService);
     this._clearState();
   }
 

addons/xterm-addon-canvas/src/TextRenderLayer.ts

@@ -12,7 +12,7 @@ import { NULL_CELL_CODE, Content, UnderlineStyle } from 'common/buffer/Constants
 import { IColorSet } from 'browser/Types';
 import { CellData } from 'common/buffer/CellData';
 import { IOptionsService, IBufferService, IDecorationService } from 'common/services/Services';
-import { ICharacterJoinerService } from 'browser/services/Services';
+import { ICharacterJoinerService, ICoreBrowserService } from 'browser/services/Services';
 import { JoinedCellData } from 'browser/services/CharacterJoinerService';
 import { color, css } from 'common/Color';
 
@@ -39,9 +39,10 @@ export class TextRenderLayer extends BaseRenderLayer {
     bufferService: IBufferService,
     optionsService: IOptionsService,
     private readonly _characterJoinerService: ICharacterJoinerService,
-    decorationService: IDecorationService
+    decorationService: IDecorationService,
+    coreBrowserService: ICoreBrowserService
   ) {
-    super(container, 'text', zIndex, alpha, colors, rendererId, bufferService, optionsService, decorationService);
+    super(container, 'text', zIndex, alpha, colors, rendererId, bufferService, optionsService, decorationService, coreBrowserService);
     this._state = new GridCache<CharData>();
   }
 
@@ -282,8 +283,8 @@ export class TextRenderLayer extends BaseRenderLayer {
           }
           switch (cell.extended.underlineStyle) {
             case UnderlineStyle.DOUBLE:
-              this._fillBottomLineAtCells(x, y, cell.getWidth(), -window.devicePixelRatio);
-              this._fillBottomLineAtCells(x, y, cell.getWidth(), window.devicePixelRatio);
+              this._fillBottomLineAtCells(x, y, cell.getWidth(), -this._coreBrowserService.dpr);
+              this._fillBottomLineAtCells(x, y, cell.getWidth(), this._coreBrowserService.dpr);
               break;
             case UnderlineStyle.CURLY:
               this._curlyUnderlineAtCell(x, y, cell.getWidth());

addons/xterm-addon-canvas/src/atlas/CharAtlasCache.ts

@@ -29,9 +29,10 @@ export function acquireCharAtlas(
   rendererId: number,
   colors: IColorSet,
   scaledCharWidth: number,
-  scaledCharHeight: number
+  scaledCharHeight: number,
+  devicePixelRatio: number
 ): BaseCharAtlas {
-  const newConfig = generateConfig(scaledCharWidth, scaledCharHeight, options, colors);
+  const newConfig = generateConfig(scaledCharWidth, scaledCharHeight, options, colors, devicePixelRatio);
 
   // Check to see if the renderer already owns this config
   for (let i = 0; i < charAtlasCache.length; i++) {

addons/xterm-addon-canvas/src/atlas/CharAtlasUtils.ts

@@ -8,7 +8,7 @@ import { DEFAULT_COLOR } from 'common/buffer/Constants';
 import { IColorSet, IPartialColorSet } from 'browser/Types';
 import { ITerminalOptions } from 'xterm';
 
-export function generateConfig(scaledCharWidth: number, scaledCharHeight: number, options: Required<ITerminalOptions>, colors: IColorSet): ICharAtlasConfig {
+export function generateConfig(scaledCharWidth: number, scaledCharHeight: number, options: Required<ITerminalOptions>, colors: IColorSet, devicePixelRatio: number): ICharAtlasConfig {
   // null out some fields that don't matter
   const clonedColors: IPartialColorSet = {
     foreground: colors.foreground,
@@ -19,7 +19,7 @@ export function generateConfig(scaledCharWidth: number, scaledCharHeight: number
     ansi: colors.ansi.slice()
   };
   return {
-    devicePixelRatio: window.devicePixelRatio,
+    devicePixelRatio,
     scaledCharWidth,
     scaledCharHeight,
     fontFamily: options.fontFamily,

addons/xterm-addon-webgl/src/WebglRenderer.ts

@@ -77,7 +77,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._core = (this._terminal as any)._core;
 
     this._renderLayers = [
-      new LinkRenderLayer(this._core.screenElement!, 2, this._colors, this._core),
+      new LinkRenderLayer(this._core.screenElement!, 2, this._colors, this._core, this._coreBrowserService),
       new CursorRenderLayer(_terminal, this._core.screenElement!, 3, this._colors, this._onRequestRedraw, this._coreBrowserService, coreService)
     ];
     this.dimensions = {
@@ -94,7 +94,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
       actualCellWidth: 0,
       actualCellHeight: 0
     };
-    this._devicePixelRatio = window.devicePixelRatio;
+    this._devicePixelRatio = this._coreBrowserService.dpr;
     this._updateDimensions();
 
     this._canvas = document.createElement('canvas');
@@ -132,13 +132,13 @@ export class WebglRenderer extends Disposable implements IRenderer {
       this._requestRedrawViewport();
     }));
 
-    this.register(observeDevicePixelDimensions(this._canvas, (w, h) => this._setCanvasDevicePixelDimensions(w, h)));
+    this.register(observeDevicePixelDimensions(this._canvas, this._coreBrowserService.window, (w, h) => this._setCanvasDevicePixelDimensions(w, h)));
 
     this._core.screenElement!.appendChild(this._canvas);
 
     this._initializeWebGLState();
 
-    this._isAttached = document.body.contains(this._core.screenElement!);
+    this._isAttached = this._coreBrowserService.window.document.body.contains(this._core.screenElement!);
   }
 
   public dispose(): void {
@@ -173,8 +173,8 @@ export class WebglRenderer extends Disposable implements IRenderer {
   public onDevicePixelRatioChange(): void {
     // If the device pixel ratio changed, the char atlas needs to be regenerated
     // and the terminal needs to refreshed
-    if (this._devicePixelRatio !== window.devicePixelRatio) {
-      this._devicePixelRatio = window.devicePixelRatio;
+    if (this._devicePixelRatio !== this._coreBrowserService.dpr) {
+      this._devicePixelRatio = this._coreBrowserService.dpr;
       this.onResize(this._terminal.cols, this._terminal.rows);
     }
   }
@@ -281,7 +281,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
       return;
     }
 
-    const atlas = acquireCharAtlas(this._terminal, this._colors, this.dimensions.scaledCellWidth, this.dimensions.scaledCellHeight, this.dimensions.scaledCharWidth, this.dimensions.scaledCharHeight);
+    const atlas = acquireCharAtlas(this._terminal, this._colors, this.dimensions.scaledCellWidth, this.dimensions.scaledCellHeight, this.dimensions.scaledCharWidth, this.dimensions.scaledCharHeight, this._coreBrowserService.dpr);
     if (!('getRasterizedGlyph' in atlas)) {
       throw new Error('The webgl renderer only works with the webgl char atlas');
     }
@@ -329,7 +329,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
 
   public renderRows(start: number, end: number): void {
     if (!this._isAttached) {
-      if (document.body.contains(this._core.screenElement!) && (this._core as any)._charSizeService.width && (this._core as any)._charSizeService.height) {
+      if (this._coreBrowserService.window.document.body.contains(this._core.screenElement!) && (this._core as any)._charSizeService.width && (this._core as any)._charSizeService.height) {
         this._updateDimensions();
         this._refreshCharAtlas();
         this._isAttached = true;

addons/xterm-addon-webgl/src/atlas/CharAtlasCache.ts

@@ -31,9 +31,10 @@ export function acquireCharAtlas(
   scaledCellWidth: number,
   scaledCellHeight: number,
   scaledCharWidth: number,
-  scaledCharHeight: number
+  scaledCharHeight: number,
+  devicePixelRatio: number
 ): WebglCharAtlas {
-  const newConfig = generateConfig(scaledCellWidth, scaledCellHeight, scaledCharWidth, scaledCharHeight, terminal, colors);
+  const newConfig = generateConfig(scaledCellWidth, scaledCellHeight, scaledCharWidth, scaledCharHeight, terminal, colors, devicePixelRatio);
 
   // Check to see if the terminal already owns this config
   for (let i = 0; i < charAtlasCache.length; i++) {

addons/xterm-addon-webgl/src/atlas/CharAtlasUtils.ts

@@ -14,7 +14,7 @@ const NULL_COLOR: IColor = {
   rgba: 0
 };
 
-export function generateConfig(scaledCellWidth: number, scaledCellHeight: number, scaledCharWidth: number, scaledCharHeight: number, terminal: Terminal, colors: IColorSet): ICharAtlasConfig {
+export function generateConfig(scaledCellWidth: number, scaledCellHeight: number, scaledCharWidth: number, scaledCharHeight: number, terminal: Terminal, colors: IColorSet, devicePixelRatio: number): ICharAtlasConfig {
   // null out some fields that don't matter
   const clonedColors: IColorSet = {
     foreground: colors.foreground,
@@ -33,7 +33,7 @@ export function generateConfig(scaledCellWidth: number, scaledCellHeight: number
   };
   return {
     customGlyphs: terminal.options.customGlyphs,
-    devicePixelRatio: window.devicePixelRatio,
+    devicePixelRatio,
     letterSpacing: terminal.options.letterSpacing,
     lineHeight: terminal.options.lineHeight,
     scaledCellWidth,

addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts

@@ -409,7 +409,7 @@ export class WebglCharAtlas implements IDisposable {
     // Draw custom characters if applicable
     let customGlyph = false;
     if (this._config.customGlyphs !== false) {
-      customGlyph = tryDrawCustomChar(this._tmpCtx, chars, padding, padding, this._config.scaledCellWidth, this._config.scaledCellHeight, this._config.fontSize);
+      customGlyph = tryDrawCustomChar(this._tmpCtx, chars, padding, padding, this._config.scaledCellWidth, this._config.scaledCellHeight, this._config.fontSize, this._config.devicePixelRatio);
     }
 
     // Whether to clear pixels based on a threshold difference between the glyph color and the
@@ -427,7 +427,7 @@ export class WebglCharAtlas implements IDisposable {
     // Draw underline
     if (underline) {
       this._tmpCtx.save();
-      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * window.devicePixelRatio / 15));
+      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * this._config.devicePixelRatio / 15));
       // When the line width is odd, draw at a 0.5 position
       const yOffset = lineWidth % 2 === 1 ? 0.5 : 0;
       this._tmpCtx.lineWidth = lineWidth;
@@ -501,12 +501,12 @@ export class WebglCharAtlas implements IDisposable {
             );
             break;
           case UnderlineStyle.DOTTED:
-            this._tmpCtx.setLineDash([window.devicePixelRatio * 2, window.devicePixelRatio]);
+            this._tmpCtx.setLineDash([this._config.devicePixelRatio * 2, this._config.devicePixelRatio]);
             this._tmpCtx.moveTo(xChLeft, yTop);
             this._tmpCtx.lineTo(xChRight, yTop);
             break;
           case UnderlineStyle.DASHED:
-            this._tmpCtx.setLineDash([window.devicePixelRatio * 4, window.devicePixelRatio * 3]);
+            this._tmpCtx.setLineDash([this._config.devicePixelRatio * 4, this._config.devicePixelRatio * 3]);
             this._tmpCtx.moveTo(xChLeft, yTop);
             this._tmpCtx.lineTo(xChRight, yTop);
             break;
@@ -543,7 +543,7 @@ export class WebglCharAtlas implements IDisposable {
             const clipRegion = new Path2D();
             clipRegion.rect(xLeft, yTop - Math.ceil(lineWidth / 2), this._config.scaledCellWidth, yBot - yTop + Math.ceil(lineWidth / 2));
             this._tmpCtx.clip(clipRegion);
-            this._tmpCtx.lineWidth = window.devicePixelRatio * 3;
+            this._tmpCtx.lineWidth = this._config.devicePixelRatio * 3;
             this._tmpCtx.strokeStyle = backgroundColor.css;
             this._tmpCtx.strokeText(chars, padding, padding + this._config.scaledCharHeight);
             this._tmpCtx.restore();
@@ -578,7 +578,7 @@ export class WebglCharAtlas implements IDisposable {
 
     // Draw strokethrough
     if (strikethrough) {
-      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * window.devicePixelRatio / 10));
+      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * this._config.devicePixelRatio / 10));
       const yOffset = this._tmpCtx.lineWidth % 2 === 1 ? 0.5 : 0; // When the width is odd, draw at 0.5 position
       this._tmpCtx.lineWidth = lineWidth;
       this._tmpCtx.strokeStyle = this._tmpCtx.fillStyle;

addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts

@@ -8,6 +8,7 @@ import { acquireCharAtlas } from '../atlas/CharAtlasCache';
 import { Terminal } from 'xterm';
 import { IColorSet } from 'browser/Types';
 import { TEXT_BASELINE } from 'browser/renderer/Constants';
+import { ICoreBrowserService } from 'browser/services/Services';
 import { IRenderDimensions } from 'browser/renderer/Types';
 import { CellData } from 'common/buffer/CellData';
 import { WebglCharAtlas } from 'atlas/WebglCharAtlas';
@@ -30,7 +31,8 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     id: string,
     zIndex: number,
     private _alpha: boolean,
-    protected _colors: IColorSet
+    protected _colors: IColorSet,
+    protected readonly _coreBrowserService: ICoreBrowserService
   ) {
     this._canvas = document.createElement('canvas');
     this._canvas.classList.add(`xterm-${id}-layer`);
@@ -93,7 +95,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     if (this._scaledCharWidth <= 0 && this._scaledCharHeight <= 0) {
       return;
     }
-    this._charAtlas = acquireCharAtlas(terminal, colorSet, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharWidth, this._scaledCharHeight);
+    this._charAtlas = acquireCharAtlas(terminal, colorSet, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharWidth, this._scaledCharHeight, this._coreBrowserService.dpr);
     this._charAtlas.warmUp();
   }
 
@@ -143,9 +145,9 @@ export abstract class BaseRenderLayer implements IRenderLayer {
   protected _fillBottomLineAtCells(x: number, y: number, width: number = 1): void {
     this._ctx.fillRect(
       x * this._scaledCellWidth,
-      (y + 1) * this._scaledCellHeight - window.devicePixelRatio - 1 /* Ensure it's drawn within the cell */,
+      (y + 1) * this._scaledCellHeight - this._coreBrowserService.dpr - 1 /* Ensure it's drawn within the cell */,
       width * this._scaledCellWidth,
-      window.devicePixelRatio);
+      this._coreBrowserService.dpr);
   }
 
   /**
@@ -158,7 +160,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     this._ctx.fillRect(
       x * this._scaledCellWidth,
       y * this._scaledCellHeight,
-      window.devicePixelRatio * width,
+      this._coreBrowserService.dpr * width,
       this._scaledCellHeight);
   }
 
@@ -169,12 +171,12 @@ export abstract class BaseRenderLayer implements IRenderLayer {
    * @param y The row to fill.
    */
   protected _strokeRectAtCell(x: number, y: number, width: number, height: number): void {
-    this._ctx.lineWidth = window.devicePixelRatio;
+    this._ctx.lineWidth = this._coreBrowserService.dpr;
     this._ctx.strokeRect(
-      x * this._scaledCellWidth + window.devicePixelRatio / 2,
-      y * this._scaledCellHeight + (window.devicePixelRatio / 2),
-      width * this._scaledCellWidth - window.devicePixelRatio,
-      (height * this._scaledCellHeight) - window.devicePixelRatio);
+      x * this._scaledCellWidth + this._coreBrowserService.dpr / 2,
+      y * this._scaledCellHeight + (this._coreBrowserService.dpr / 2),
+      width * this._scaledCellWidth - this._coreBrowserService.dpr,
+      (height * this._scaledCellHeight) - this._coreBrowserService.dpr);
   }
 
   /**
@@ -258,7 +260,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     const fontWeight = isBold ? terminal.options.fontWeightBold : terminal.options.fontWeight;
     const fontStyle = isItalic ? 'italic' : '';
 
-    return `${fontStyle} ${fontWeight} ${terminal.options.fontSize! * window.devicePixelRatio}px ${terminal.options.fontFamily}`;
+    return `${fontStyle} ${fontWeight} ${terminal.options.fontSize! * this._coreBrowserService.dpr}px ${terminal.options.fontFamily}`;
   }
 }
 

addons/xterm-addon-webgl/src/renderLayer/CursorRenderLayer.ts

@@ -38,10 +38,10 @@ export class CursorRenderLayer extends BaseRenderLayer {
     zIndex: number,
     colors: IColorSet,
     private _onRequestRefreshRowsEvent: IEventEmitter<IRequestRedrawEvent>,
-    private readonly _coreBrowserService: ICoreBrowserService,
+    coreBrowserService: ICoreBrowserService,
     private readonly _coreService: ICoreService
   ) {
-    super(container, 'cursor', zIndex, true, colors);
+    super(container, 'cursor', zIndex, true, colors, coreBrowserService);
     this._state = {
       x: 0,
       y: 0,
@@ -195,7 +195,7 @@ export class CursorRenderLayer extends BaseRenderLayer {
   private _clearCursor(): void {
     if (this._state) {
       // Avoid potential rounding errors when device pixel ratio is less than 1
-      if (window.devicePixelRatio < 1) {
+      if (this._coreBrowserService.dpr < 1) {
         this._clearAll();
       } else {
         this._clearCells(this._state.x, this._state.y, this._state.width, 1);
@@ -257,10 +257,10 @@ class CursorBlinkStateManager {
 
   constructor(
     private _renderCallback: () => void,
-    coreBrowserService: ICoreBrowserService
+    private _coreBrowserService: ICoreBrowserService
   ) {
     this.isCursorVisible = true;
-    if (coreBrowserService.isFocused) {
+    if (this._coreBrowserService.isFocused) {
       this._restartInterval();
     }
   }
@@ -269,15 +269,15 @@ class CursorBlinkStateManager {
 
   public dispose(): void {
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
     if (this._blinkStartTimeout) {
-      window.clearTimeout(this._blinkStartTimeout);
+      this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
       this._blinkStartTimeout = undefined;
     }
     if (this._animationFrame) {
-      window.cancelAnimationFrame(this._animationFrame);
+      this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
   }
@@ -291,7 +291,7 @@ class CursorBlinkStateManager {
     // Force a cursor render to ensure it's visible and in the correct position
     this.isCursorVisible = true;
     if (!this._animationFrame) {
-      this._animationFrame = window.requestAnimationFrame(() => {
+      this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
         this._renderCallback();
         this._animationFrame = undefined;
       });
@@ -301,7 +301,7 @@ class CursorBlinkStateManager {
   private _restartInterval(timeToStart: number = BLINK_INTERVAL): void {
     // Clear any existing interval
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
 
@@ -309,7 +309,7 @@ class CursorBlinkStateManager {
     // the regular interval is setup in order to support restarting the blink
     // animation in a lightweight way (without thrashing clearInterval and
     // setInterval).
-    this._blinkStartTimeout = window.setTimeout(() => {
+    this._blinkStartTimeout = this._coreBrowserService.window.setTimeout(() => {
       // Check if another animation restart was requested while this was being
       // started
       if (this._animationTimeRestarted) {
@@ -323,13 +323,13 @@ class CursorBlinkStateManager {
 
       // Hide the cursor
       this.isCursorVisible = false;
-      this._animationFrame = window.requestAnimationFrame(() => {
+      this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
         this._renderCallback();
         this._animationFrame = undefined;
       });
 
       // Setup the blink interval
-      this._blinkInterval = window.setInterval(() => {
+      this._blinkInterval = this._coreBrowserService.window.setInterval(() => {
         // Adjust the animation time if it was restarted
         if (this._animationTimeRestarted) {
           // calc time diff
@@ -342,7 +342,7 @@ class CursorBlinkStateManager {
 
         // Invert visibility and render
         this.isCursorVisible = !this.isCursorVisible;
-        this._animationFrame = window.requestAnimationFrame(() => {
+        this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
           this._renderCallback();
           this._animationFrame = undefined;
         });
@@ -353,15 +353,15 @@ class CursorBlinkStateManager {
   public pause(): void {
     this.isCursorVisible = true;
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
     if (this._blinkStartTimeout) {
-      window.clearTimeout(this._blinkStartTimeout);
+      this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
       this._blinkStartTimeout = undefined;
     }
     if (this._animationFrame) {
-      window.cancelAnimationFrame(this._animationFrame);
+      this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
   }

addons/xterm-addon-webgl/src/renderLayer/LinkRenderLayer.ts

@@ -9,12 +9,19 @@ import { INVERTED_DEFAULT_COLOR } from 'browser/renderer/Constants';
 import { is256Color } from '../atlas/CharAtlasUtils';
 import { ITerminal, IColorSet, ILinkifierEvent } from 'browser/Types';
 import { IRenderDimensions } from 'browser/renderer/Types';
+import { ICoreBrowserService } from 'browser/services/Services';
 
 export class LinkRenderLayer extends BaseRenderLayer {
   private _state: ILinkifierEvent | undefined;
 
-  constructor(container: HTMLElement, zIndex: number, colors: IColorSet, terminal: ITerminal) {
-    super(container, 'link', zIndex, true, colors);
+  constructor(
+    container: HTMLElement,
+    zIndex: number,
+    colors: IColorSet,
+    terminal: ITerminal,
+    coreBrowserService: ICoreBrowserService
+  ) {
+    super(container, 'link', zIndex, true, colors, coreBrowserService);
 
     terminal.linkifier2.onShowLinkUnderline(e => this._onShowLinkUnderline(e));
     terminal.linkifier2.onHideLinkUnderline(e => this._onHideLinkUnderline(e));

src/browser/AccessibilityManager.ts

@@ -98,7 +98,7 @@ export class AccessibilityManager extends Disposable {
     this.register(this._terminal.onBlur(() => this._clearLiveRegion()));
     this.register(this._renderService.onDimensionsChange(() => this._refreshRowsDimensions()));
 
-    this._screenDprMonitor = new ScreenDprMonitor();
+    this._screenDprMonitor = new ScreenDprMonitor(window);
     this.register(this._screenDprMonitor);
     this._screenDprMonitor.setListener(() => this._refreshRowsDimensions());
     // This shouldn't be needed on modern browsers but is present in case the

src/browser/RenderDebouncer.ts

@@ -16,13 +16,14 @@ export class RenderDebouncer implements IRenderDebouncerWithCallback {
   private _refreshCallbacks: FrameRequestCallback[] = [];
 
   constructor(
+    private _parentWindow: Window,
     private _renderCallback: (start: number, end: number) => void
   ) {
   }
 
   public dispose(): void {
     if (this._animationFrame) {
-      window.cancelAnimationFrame(this._animationFrame);
+      this._parentWindow.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
   }
@@ -30,7 +31,7 @@ export class RenderDebouncer implements IRenderDebouncerWithCallback {
   public addRefreshCallback(callback: FrameRequestCallback): number {
     this._refreshCallbacks.push(callback);
     if (!this._animationFrame) {
-      this._animationFrame = window.requestAnimationFrame(() => this._innerRefresh());
+      this._animationFrame = this._parentWindow.requestAnimationFrame(() => this._innerRefresh());
     }
     return this._animationFrame;
   }
@@ -48,7 +49,7 @@ export class RenderDebouncer implements IRenderDebouncerWithCallback {
       return;
     }
 
-    this._animationFrame = window.requestAnimationFrame(() => this._innerRefresh());
+    this._animationFrame = this._parentWindow.requestAnimationFrame(() => this._innerRefresh());
   }
 
   private _innerRefresh(): void {

src/browser/ScreenDprMonitor.ts

@@ -18,11 +18,16 @@ export type ScreenDprListener = (newDevicePixelRatio?: number, oldDevicePixelRat
  * monitor with a different DPI.
  */
 export class ScreenDprMonitor extends Disposable {
-  private _currentDevicePixelRatio: number = window.devicePixelRatio;
+  private _currentDevicePixelRatio: number;
   private _outerListener: ((this: MediaQueryList, ev: MediaQueryListEvent) => any) | undefined;
   private _listener: ScreenDprListener | undefined;
   private _resolutionMediaMatchList: MediaQueryList | undefined;
 
+  constructor(private _parentWindow: Window) {
+    super();
+    this._currentDevicePixelRatio = this._parentWindow.devicePixelRatio;
+  }
+
   public setListener(listener: ScreenDprListener): void {
     if (this._listener) {
       this.clearListener();
@@ -32,7 +37,7 @@ export class ScreenDprMonitor extends Disposable {
       if (!this._listener) {
         return;
       }
-      this._listener(window.devicePixelRatio, this._currentDevicePixelRatio);
+      this._listener(this._parentWindow.devicePixelRatio, this._currentDevicePixelRatio);
       this._updateDpr();
     };
     this._updateDpr();
@@ -52,8 +57,8 @@ export class ScreenDprMonitor extends Disposable {
     this._resolutionMediaMatchList?.removeListener(this._outerListener);
 
     // Add listeners for new DPR
-    this._currentDevicePixelRatio = window.devicePixelRatio;
-    this._resolutionMediaMatchList = window.matchMedia(`screen and (resolution: ${window.devicePixelRatio}dppx)`);
+    this._currentDevicePixelRatio = this._parentWindow.devicePixelRatio;
+    this._resolutionMediaMatchList = this._parentWindow.matchMedia(`screen and (resolution: ${this._parentWindow.devicePixelRatio}dppx)`);
     this._resolutionMediaMatchList.addListener(this._outerListener);
   }
 

src/browser/Terminal.ts

@@ -495,7 +495,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
     this.register(addDisposableDomListener(this.textarea, 'blur', () => this._onTextAreaBlur()));
     this._helperContainer.appendChild(this.textarea);
 
-    this._coreBrowserService = this._instantiationService.createInstance(CoreBrowserService, this.textarea);
+    this._coreBrowserService = this._instantiationService.createInstance(CoreBrowserService, this.textarea, this._document.defaultView ?? window);
     this._instantiationService.setService(ICoreBrowserService, this._coreBrowserService);
 
     this._charSizeService = this._instantiationService.createInstance(CharSizeService, this._document, this._helperContainer);

src/browser/TestUtils.test.ts

@@ -343,6 +343,10 @@ export class MockCompositionHelper implements ICompositionHelper {
 export class MockCoreBrowserService implements ICoreBrowserService {
   public serviceBrand: undefined;
   public isFocused: boolean = true;
+  public get window(): Window & typeof globalThis {
+    throw Error('Window object not available in tests');
+  }
+  public dpr: number = 1;
 }
 
 export class MockCharSizeService implements ICharSizeService {

src/browser/Viewport.ts

@@ -6,7 +6,7 @@
 import { Disposable } from 'common/Lifecycle';
 import { addDisposableDomListener } from 'browser/Lifecycle';
 import { IColorSet, IViewport } from 'browser/Types';
-import { ICharSizeService, IRenderService } from 'browser/services/Services';
+import { ICharSizeService, ICoreBrowserService, IRenderService } from 'browser/services/Services';
 import { IBufferService, IOptionsService } from 'common/services/Services';
 import { IBuffer } from 'common/buffer/Types';
 import { IRenderDimensions } from 'browser/renderer/Types';
@@ -56,7 +56,8 @@ export class Viewport extends Disposable implements IViewport {
     @IBufferService private readonly _bufferService: IBufferService,
     @IOptionsService private readonly _optionsService: IOptionsService,
     @ICharSizeService private readonly _charSizeService: ICharSizeService,
-    @IRenderService private readonly _renderService: IRenderService
+    @IRenderService private readonly _renderService: IRenderService,
+    @ICoreBrowserService private readonly _coreBrowserService: ICoreBrowserService
   ) {
     super();
 
@@ -88,18 +89,18 @@ export class Viewport extends Disposable implements IViewport {
     if (immediate) {
       this._innerRefresh();
       if (this._refreshAnimationFrame !== null) {
-        cancelAnimationFrame(this._refreshAnimationFrame);
+        this._coreBrowserService.window.cancelAnimationFrame(this._refreshAnimationFrame);
       }
       return;
     }
     if (this._refreshAnimationFrame === null) {
-      this._refreshAnimationFrame = requestAnimationFrame(() => this._innerRefresh());
+      this._refreshAnimationFrame = this._coreBrowserService.window.requestAnimationFrame(() => this._innerRefresh());
     }
   }
 
   private _innerRefresh(): void {
     if (this._charSizeService.height > 0) {
-      this._currentRowHeight = this._renderService.dimensions.scaledCellHeight / window.devicePixelRatio;
+      this._currentRowHeight = this._renderService.dimensions.scaledCellHeight / this._coreBrowserService.dpr;
       this._currentScaledCellHeight = this._renderService.dimensions.scaledCellHeight;
       this._lastRecordedViewportHeight = this._viewportElement.offsetHeight;
       const newBufferHeight = Math.round(this._currentRowHeight * this._lastRecordedBufferLength) + (this._lastRecordedViewportHeight - this._renderService.dimensions.canvasHeight);
@@ -191,7 +192,7 @@ export class Viewport extends Disposable implements IViewport {
 
     // Continue or finish smooth scroll
     if (percent < 1) {
-      window.requestAnimationFrame(() => this._smoothScroll());
+      this._coreBrowserService.window.requestAnimationFrame(() => this._smoothScroll());
     } else {
       this._clearSmoothScrollState();
     }

src/browser/decorations/OverviewRulerRenderer.ts

@@ -5,7 +5,7 @@
 
 import { ColorZoneStore, IColorZone, IColorZoneStore } from 'browser/decorations/ColorZoneStore';
 import { addDisposableDomListener } from 'browser/Lifecycle';
-import { IRenderService } from 'browser/services/Services';
+import { ICoreBrowserService, IRenderService } from 'browser/services/Services';
 import { Disposable } from 'common/Lifecycle';
 import { IBufferService, IDecorationService, IOptionsService } from 'common/services/Services';
 
@@ -51,7 +51,8 @@ export class OverviewRulerRenderer extends Disposable {
     @IBufferService private readonly _bufferService: IBufferService,
     @IDecorationService private readonly _decorationService: IDecorationService,
     @IRenderService private readonly _renderService: IRenderService,
-    @IOptionsService private readonly _optionsService: IOptionsService
+    @IOptionsService private readonly _optionsService: IOptionsService,
+    @ICoreBrowserService private readonly _coreBrowseService: ICoreBrowserService
   ) {
     super();
     this._canvas = document.createElement('canvas');
@@ -112,7 +113,7 @@ export class OverviewRulerRenderer extends Disposable {
       }
     }));
     // device pixel ratio changed
-    this.register(addDisposableDomListener(window, 'resize', () => {
+    this.register(addDisposableDomListener(this._coreBrowseService.window, 'resize', () => {
       this._queueRefresh(true);
     }));
     // set the canvas dimensions
@@ -142,11 +143,11 @@ export class OverviewRulerRenderer extends Disposable {
   }
 
   private _refreshDrawHeightConstants(): void {
-    drawHeight.full = Math.round(2 * window.devicePixelRatio);
+    drawHeight.full = Math.round(2 * this._coreBrowseService.dpr);
     // Calculate actual pixels per line
     const pixelsPerLine = this._canvas.height / this._bufferService.buffer.lines.length;
     // Clamp actual pixels within a range
-    const nonFullHeight = Math.round(Math.max(Math.min(pixelsPerLine, 12), 6) * window.devicePixelRatio);
+    const nonFullHeight = Math.round(Math.max(Math.min(pixelsPerLine, 12), 6) * this._coreBrowseService.dpr);
     drawHeight.left = nonFullHeight;
     drawHeight.center = nonFullHeight;
     drawHeight.right = nonFullHeight;
@@ -164,9 +165,9 @@ export class OverviewRulerRenderer extends Disposable {
 
   private _refreshCanvasDimensions(): void {
     this._canvas.style.width = `${this._width}px`;
-    this._canvas.width = Math.round(this._width * window.devicePixelRatio);
+    this._canvas.width = Math.round(this._width * this._coreBrowseService.dpr);
     this._canvas.style.height = `${this._screenElement.clientHeight}px`;
-    this._canvas.height = Math.round(this._screenElement.clientHeight * window.devicePixelRatio);
+    this._canvas.height = Math.round(this._screenElement.clientHeight * this._coreBrowseService.dpr);
     this._refreshDrawConstants();
     this._refreshColorZonePadding();
   }
@@ -220,7 +221,7 @@ export class OverviewRulerRenderer extends Disposable {
     if (this._animationFrame !== undefined) {
       return;
     }
-    this._animationFrame = window.requestAnimationFrame(() => {
+    this._animationFrame = this._coreBrowseService.window.requestAnimationFrame(() => {
       this._refreshDecorations();
       this._animationFrame = undefined;
     });

src/browser/renderer/CustomGlyphs.ts

@@ -383,7 +383,8 @@ export function tryDrawCustomChar(
   yOffset: number,
   scaledCellWidth: number,
   scaledCellHeight: number,
-  fontSize: number
+  fontSize: number,
+  devicePixelRatio: number
 ): boolean {
   const blockElementDefinition = blockElementDefinitions[c];
   if (blockElementDefinition) {
@@ -399,13 +400,13 @@ export function tryDrawCustomChar(
 
   const boxDrawingDefinition = boxDrawingDefinitions[c];
   if (boxDrawingDefinition) {
-    drawBoxDrawingChar(ctx, boxDrawingDefinition, xOffset, yOffset, scaledCellWidth, scaledCellHeight);
+    drawBoxDrawingChar(ctx, boxDrawingDefinition, xOffset, yOffset, scaledCellWidth, scaledCellHeight, devicePixelRatio);
     return true;
   }
 
   const powerlineDefinition = powerlineDefinitions[c];
   if (powerlineDefinition) {
-    drawPowerlineChar(ctx, powerlineDefinition, xOffset, yOffset, scaledCellWidth, scaledCellHeight, fontSize);
+    drawPowerlineChar(ctx, powerlineDefinition, xOffset, yOffset, scaledCellWidth, scaledCellHeight, fontSize, devicePixelRatio);
     return true;
   }
 
@@ -540,12 +541,13 @@ function drawBoxDrawingChar(
   xOffset: number,
   yOffset: number,
   scaledCellWidth: number,
-  scaledCellHeight: number
+  scaledCellHeight: number,
+  devicePixelRatio: number
 ): void {
   ctx.strokeStyle = ctx.fillStyle;
   for (const [fontWeight, instructions] of Object.entries(charDefinition)) {
     ctx.beginPath();
-    ctx.lineWidth = window.devicePixelRatio * Number.parseInt(fontWeight);
+    ctx.lineWidth = devicePixelRatio * Number.parseInt(fontWeight);
     let actualInstructions: string;
     if (typeof instructions === 'function') {
       const xp = .15;
@@ -565,7 +567,7 @@ function drawBoxDrawingChar(
       if (!args[0] || !args[1]) {
         continue;
       }
-      f(ctx, translateArgs(args, scaledCellWidth, scaledCellHeight, xOffset, yOffset, true));
+      f(ctx, translateArgs(args, scaledCellWidth, scaledCellHeight, xOffset, yOffset, true, devicePixelRatio));
     }
     ctx.stroke();
     ctx.closePath();
@@ -579,12 +581,13 @@ function drawPowerlineChar(
   yOffset: number,
   scaledCellWidth: number,
   scaledCellHeight: number,
-  fontSize: number
+  fontSize: number,
+  devicePixelRatio: number
 ): void {
   ctx.beginPath();
   // Scale the stroke with DPR and font size
   const cssLineWidth = fontSize / 12;
-  ctx.lineWidth = window.devicePixelRatio * cssLineWidth;
+  ctx.lineWidth = devicePixelRatio * cssLineWidth;
   for (const instruction of charDefinition.d.split(' ')) {
     const type = instruction[0];
     const f = svgToCanvasInstructionMap[type];
@@ -626,7 +629,7 @@ const svgToCanvasInstructionMap: { [index: string]: any } = {
   'M': (ctx: CanvasRenderingContext2D, args: number[]) => ctx.moveTo(args[0], args[1])
 };
 
-function translateArgs(args: string[], cellWidth: number, cellHeight: number, xOffset: number, yOffset: number, doClamp: boolean, leftPadding: number = 0, rightPadding: number = 0): number[] {
+function translateArgs(args: string[], cellWidth: number, cellHeight: number, xOffset: number, yOffset: number, doClamp: boolean, devicePixelRatio: number, leftPadding: number = 0, rightPadding: number = 0): number[] {
   const result = args.map(e => parseFloat(e) || parseInt(e));
 
   if (result.length < 2) {
@@ -635,14 +638,14 @@ function translateArgs(args: string[], cellWidth: number, cellHeight: number, xO
 
   for (let x = 0; x < result.length; x += 2) {
     // Translate from 0-1 to 0-cellWidth
-    result[x] *= cellWidth - (leftPadding * window.devicePixelRatio) - (rightPadding * window.devicePixelRatio);
+    result[x] *= cellWidth - (leftPadding * devicePixelRatio) - (rightPadding * devicePixelRatio);
     // Ensure coordinate doesn't escape cell bounds and round to the nearest 0.5 to ensure a crisp
     // line at 100% devicePixelRatio
     if (doClamp && result[x] !== 0) {
       result[x] = clamp(Math.round(result[x] + 0.5) - 0.5, cellWidth, 0);
     }
     // Apply the cell's offset (ie. x*cellWidth)
-    result[x] += xOffset + (leftPadding * window.devicePixelRatio);
+    result[x] += xOffset + (leftPadding * devicePixelRatio);
   }
 
   for (let y = 1; y < result.length; y += 2) {

src/browser/renderer/DevicePixelObserver.ts

@@ -6,12 +6,12 @@
 import { toDisposable } from 'common/Lifecycle';
 import { IDisposable } from 'common/Types';
 
-export function observeDevicePixelDimensions(element: HTMLElement, callback: (deviceWidth: number, deviceHeight: number) => void): IDisposable {
+export function observeDevicePixelDimensions(element: HTMLElement, parentWindow: Window & typeof globalThis, callback: (deviceWidth: number, deviceHeight: number) => void): IDisposable {
   // Observe any resizes to the element and extract the actual pixel size of the element if the
   // devicePixelContentBoxSize API is supported. This allows correcting rounding errors when
   // converting between CSS pixels and device pixels which causes blurry rendering when device
   // pixel ratio is not a round number.
-  let observer: ResizeObserver | undefined = new ResizeObserver((entries) => {
+  let observer: ResizeObserver | undefined = new parentWindow.ResizeObserver((entries) => {
     const entry = entries.find((entry) => entry.target === element);
     if (!entry) {
       return;

src/browser/renderer/dom/DomRenderer.ts

@@ -8,7 +8,7 @@ import { BOLD_CLASS, ITALIC_CLASS, CURSOR_CLASS, CURSOR_STYLE_BLOCK_CLASS, CURSO
 import { INVERTED_DEFAULT_COLOR } from 'browser/renderer/Constants';
 import { Disposable } from 'common/Lifecycle';
 import { IColorSet, ILinkifierEvent, ILinkifier2 } from 'browser/Types';
-import { ICharSizeService } from 'browser/services/Services';
+import { ICharSizeService, ICoreBrowserService } from 'browser/services/Services';
 import { IOptionsService, IBufferService, IInstantiationService } from 'common/services/Services';
 import { EventEmitter, IEvent } from 'common/EventEmitter';
 import { color } from 'common/Color';
@@ -51,7 +51,8 @@ export class DomRenderer extends Disposable implements IRenderer {
     @IInstantiationService instantiationService: IInstantiationService,
     @ICharSizeService private readonly _charSizeService: ICharSizeService,
     @IOptionsService private readonly _optionsService: IOptionsService,
-    @IBufferService private readonly _bufferService: IBufferService
+    @IBufferService private readonly _bufferService: IBufferService,
+    @ICoreBrowserService private readonly _coreBrowserService: ICoreBrowserService
   ) {
     super();
     this._rowContainer = document.createElement('div');
@@ -101,16 +102,17 @@ export class DomRenderer extends Disposable implements IRenderer {
   }
 
   private _updateDimensions(): void {
-    this.dimensions.scaledCharWidth = this._charSizeService.width * window.devicePixelRatio;
-    this.dimensions.scaledCharHeight = Math.ceil(this._charSizeService.height * window.devicePixelRatio);
+    const dpr = this._coreBrowserService.dpr;
+    this.dimensions.scaledCharWidth = this._charSizeService.width * dpr;
+    this.dimensions.scaledCharHeight = Math.ceil(this._charSizeService.height * dpr);
     this.dimensions.scaledCellWidth = this.dimensions.scaledCharWidth + Math.round(this._optionsService.rawOptions.letterSpacing);
     this.dimensions.scaledCellHeight = Math.floor(this.dimensions.scaledCharHeight * this._optionsService.rawOptions.lineHeight);
     this.dimensions.scaledCharLeft = 0;
     this.dimensions.scaledCharTop = 0;
     this.dimensions.scaledCanvasWidth = this.dimensions.scaledCellWidth * this._bufferService.cols;
     this.dimensions.scaledCanvasHeight = this.dimensions.scaledCellHeight * this._bufferService.rows;
-    this.dimensions.canvasWidth = Math.round(this.dimensions.scaledCanvasWidth / window.devicePixelRatio);
-    this.dimensions.canvasHeight = Math.round(this.dimensions.scaledCanvasHeight / window.devicePixelRatio);
+    this.dimensions.canvasWidth = Math.round(this.dimensions.scaledCanvasWidth / dpr);
+    this.dimensions.canvasHeight = Math.round(this.dimensions.scaledCanvasHeight / dpr);
     this.dimensions.actualCellWidth = this.dimensions.canvasWidth / this._bufferService.cols;
     this.dimensions.actualCellHeight = this.dimensions.canvasHeight / this._bufferService.rows;
 

src/browser/services/CoreBrowserService.ts

@@ -9,12 +9,17 @@ export class CoreBrowserService implements ICoreBrowserService {
   public serviceBrand: undefined;
 
   constructor(
-    private _textarea: HTMLTextAreaElement
+    private _textarea: HTMLTextAreaElement,
+    public readonly window: Window & typeof globalThis
   ) {
   }
 
+  public get dpr(): number {
+    return this.window.devicePixelRatio;
+  }
+
   public get isFocused(): boolean {
-    const docOrShadowRoot = this._textarea.getRootNode ? this._textarea.getRootNode() as Document | ShadowRoot : document;
-    return docOrShadowRoot.activeElement === this._textarea && document.hasFocus();
+    const docOrShadowRoot = this._textarea.getRootNode ? this._textarea.getRootNode() as Document | ShadowRoot : this._textarea.ownerDocument;
+    return docOrShadowRoot.activeElement === this._textarea && this._textarea.ownerDocument.hasFocus();
   }
 }

src/browser/services/RenderService.ts

@@ -11,7 +11,7 @@ import { ScreenDprMonitor } from 'browser/ScreenDprMonitor';
 import { addDisposableDomListener } from 'browser/Lifecycle';
 import { IColorSet, IRenderDebouncerWithCallback } from 'browser/Types';
 import { IOptionsService, IBufferService, IDecorationService } from 'common/services/Services';
-import { ICharSizeService, IRenderService } from 'browser/services/Services';
+import { ICharSizeService, ICoreBrowserService, IRenderService } from 'browser/services/Services';
 
 interface ISelectionState {
   start: [number, number] | undefined;
@@ -55,16 +55,17 @@ export class RenderService extends Disposable implements IRenderService {
     @IOptionsService optionsService: IOptionsService,
     @ICharSizeService private readonly _charSizeService: ICharSizeService,
     @IDecorationService decorationService: IDecorationService,
-    @IBufferService bufferService: IBufferService
+    @IBufferService bufferService: IBufferService,
+    @ICoreBrowserService coreBrowserService: ICoreBrowserService
   ) {
     super();
 
     this.register({ dispose: () => this._renderer.dispose() });
 
-    this._renderDebouncer = new RenderDebouncer((start, end) => this._renderRows(start, end));
+    this._renderDebouncer = new RenderDebouncer(coreBrowserService.window, (start, end) => this._renderRows(start, end));
     this.register(this._renderDebouncer);
 
-    this._screenDprMonitor = new ScreenDprMonitor();
+    this._screenDprMonitor = new ScreenDprMonitor(coreBrowserService.window);
     this._screenDprMonitor.setListener(() => this.onDevicePixelRatioChange());
     this.register(this._screenDprMonitor);
 
@@ -84,12 +85,12 @@ export class RenderService extends Disposable implements IRenderService {
 
     // dprchange should handle this case, we need this as well for browsers that don't support the
     // matchMedia query.
-    this.register(addDisposableDomListener(window, 'resize', () => this.onDevicePixelRatioChange()));
+    this.register(addDisposableDomListener(coreBrowserService.window, 'resize', () => this.onDevicePixelRatioChange()));
 
     // Detect whether IntersectionObserver is detected and enable renderer pause
     // and resume based on terminal visibility if so
-    if ('IntersectionObserver' in window) {
-      const observer = new IntersectionObserver(e => this._onIntersectionChange(e[e.length - 1]), { threshold: 0 });
+    if ('IntersectionObserver' in coreBrowserService.window) {
+      const observer = new coreBrowserService.window.IntersectionObserver(e => this._onIntersectionChange(e[e.length - 1]), { threshold: 0 });
       observer.observe(screenElement);
       this.register({ dispose: () => observer.disconnect() });
     }

src/browser/services/SelectionService.test.ts

@@ -10,7 +10,7 @@ import { IBufferLine } from 'common/Types';
 import { MockBufferService, MockOptionsService, MockCoreService } from 'common/TestUtils.test';
 import { BufferLine } from 'common/buffer/BufferLine';
 import { IBufferService, IOptionsService } from 'common/services/Services';
-import { MockMouseService, MockRenderService } from 'browser/TestUtils.test';
+import { MockCoreBrowserService, MockMouseService, MockRenderService } from 'browser/TestUtils.test';
 import { CellData } from 'common/buffer/CellData';
 import { IBuffer } from 'common/buffer/Types';
 import { IRenderService } from 'browser/services/Services';
@@ -21,7 +21,7 @@ class TestSelectionService extends SelectionService {
     optionsService: IOptionsService,
     renderService: IRenderService
   ) {
-    super(null!, null!, null!, bufferService, new MockCoreService(), new MockMouseService(), optionsService, renderService);
+    super(null!, null!, null!, bufferService, new MockCoreService(), new MockMouseService(), optionsService, renderService, new MockCoreBrowserService());
   }
 
   public get model(): SelectionModel { return this._model; }

src/browser/services/SelectionService.ts

@@ -10,7 +10,7 @@ import * as Browser from 'common/Platform';
 import { SelectionModel } from 'browser/selection/SelectionModel';
 import { CellData } from 'common/buffer/CellData';
 import { EventEmitter, IEvent } from 'common/EventEmitter';
-import { IMouseService, ISelectionService, IRenderService } from 'browser/services/Services';
+import { IMouseService, ISelectionService, IRenderService, ICoreBrowserService } from 'browser/services/Services';
 import { IBufferRange, ILinkifier2 } from 'browser/Types';
 import { IBufferService, IOptionsService, ICoreService } from 'common/services/Services';
 import { getCoordsRelativeToElement } from 'browser/input/Mouse';
@@ -128,7 +128,8 @@ export class SelectionService extends Disposable implements ISelectionService {
     @ICoreService private readonly _coreService: ICoreService,
     @IMouseService private readonly _mouseService: IMouseService,
     @IOptionsService private readonly _optionsService: IOptionsService,
-    @IRenderService private readonly _renderService: IRenderService
+    @IRenderService private readonly _renderService: IRenderService,
+    @ICoreBrowserService private readonly _coreBrowserService: ICoreBrowserService
   ) {
     super();
 
@@ -270,7 +271,7 @@ export class SelectionService extends Disposable implements ISelectionService {
   public refresh(isLinuxMouseSelection?: boolean): void {
     // Queue the refresh for the renderer
     if (!this._refreshAnimationFrame) {
-      this._refreshAnimationFrame = window.requestAnimationFrame(() => this._refresh());
+      this._refreshAnimationFrame = this._coreBrowserService.window.requestAnimationFrame(() => this._refresh());
     }
 
     // If the platform is Linux and the refresh call comes from a mouse event,
@@ -406,7 +407,7 @@ export class SelectionService extends Disposable implements ISelectionService {
    * @param event The mouse event.
    */
   private _getMouseEventScrollAmount(event: MouseEvent): number {
-    let offset = getCoordsRelativeToElement(window, event, this._screenElement)[1];
+    let offset = getCoordsRelativeToElement(this._coreBrowserService.window, event, this._screenElement)[1];
     const terminalHeight = this._renderService.dimensions.canvasHeight;
     if (offset >= 0 && offset <= terminalHeight) {
       return 0;
@@ -491,7 +492,7 @@ export class SelectionService extends Disposable implements ISelectionService {
       this._screenElement.ownerDocument.addEventListener('mousemove', this._mouseMoveListener);
       this._screenElement.ownerDocument.addEventListener('mouseup', this._mouseUpListener);
     }
-    this._dragScrollIntervalTimer = window.setInterval(() => this._dragScroll(), DRAG_SCROLL_INTERVAL);
+    this._dragScrollIntervalTimer = this._coreBrowserService.window.setInterval(() => this._dragScroll(), DRAG_SCROLL_INTERVAL);
   }
 
   /**
@@ -502,7 +503,7 @@ export class SelectionService extends Disposable implements ISelectionService {
       this._screenElement.ownerDocument.removeEventListener('mousemove', this._mouseMoveListener);
       this._screenElement.ownerDocument.removeEventListener('mouseup', this._mouseUpListener);
     }
-    clearInterval(this._dragScrollIntervalTimer);
+    this._coreBrowserService.window.clearInterval(this._dragScrollIntervalTimer);
     this._dragScrollIntervalTimer = undefined;
   }
 

src/browser/services/Services.ts

@@ -28,6 +28,16 @@ export interface ICoreBrowserService {
   serviceBrand: undefined;
 
   readonly isFocused: boolean;
+  /**
+   * Parent window that the terminal is rendered into. DOM and rendering APIs
+   * (e.g. requestAnimationFrame) should be invoked in the context of this
+   * window.
+   */
+  readonly window: Window & typeof globalThis;
+  /**
+   * Helper for getting the devicePixelRatio of the parent window.
+   */
+  readonly dpr: number;
 }
 
 export const IMouseService = createDecorator<IMouseService>('MouseService');