diff --git a/addons/xterm-addon-webgl/src/WebglRenderer.ts b/addons/xterm-addon-webgl/src/WebglRenderer.ts
index 326329186..0333fd208 100644
--- a/addons/xterm-addon-webgl/src/WebglRenderer.ts
+++ b/addons/xterm-addon-webgl/src/WebglRenderer.ts
@@ -173,7 +173,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._renderLayers.forEach(l => l.onFocus(this._terminal));
   }
 
-  public onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void {
+  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
     this._renderLayers.forEach(l => l.onSelectionChanged(this._terminal, start, end, columnSelectMode));
 
     this._updateSelectionModel(start, end, columnSelectMode);
@@ -295,7 +295,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._rectangleRenderer.updateBackgrounds(this._model);
   }
 
-  private _updateSelectionModel(start: [number, number], end: [number, number], columnSelectMode: boolean): void {
+  private _updateSelectionModel(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
     const terminal = this._terminal;
 
     // Selection does not exist
diff --git a/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts b/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts
index 93f844927..da3b4d418 100644
--- a/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts
+++ b/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts
@@ -58,7 +58,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
   public onFocus(terminal: Terminal): void {}
   public onCursorMove(terminal: Terminal): void {}
   public onGridChanged(terminal: Terminal, startRow: number, endRow: number): void {}
-  public onSelectionChanged(terminal: Terminal, start: [number, number], end: [number, number], columnSelectMode: boolean = false): void {}
+  public onSelectionChanged(terminal: Terminal, start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {}
 
   public setColors(terminal: Terminal, colorSet: IColorSet): void {
     this._refreshCharAtlas(terminal, colorSet);
diff --git a/addons/xterm-addon-webgl/src/renderLayer/Types.ts b/addons/xterm-addon-webgl/src/renderLayer/Types.ts
index 148ea4695..70acff340 100644
--- a/addons/xterm-addon-webgl/src/renderLayer/Types.ts
+++ b/addons/xterm-addon-webgl/src/renderLayer/Types.ts
@@ -42,7 +42,7 @@ export interface IRenderLayer extends IDisposable {
   /**
    * Calls when the selection changes.
    */
-  onSelectionChanged(terminal: Terminal, start: [number, number], end: [number, number], columnSelectMode: boolean): void;
+  onSelectionChanged(terminal: Terminal, start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
 
   /**
    * Registers a handler to join characters to render as a group
diff --git a/src/browser/RenderDebouncer.ts b/src/browser/RenderDebouncer.ts
index 27c866dfd..814afcef4 100644
--- a/src/browser/RenderDebouncer.ts
+++ b/src/browser/RenderDebouncer.ts
@@ -49,15 +49,15 @@ export class RenderDebouncer implements IDisposable {
     }
 
     // Clamp values
-    this._rowStart = Math.max(this._rowStart, 0);
-    this._rowEnd = Math.min(this._rowEnd, this._rowCount - 1);
+    const start = Math.max(this._rowStart, 0);
+    const end = Math.min(this._rowEnd, this._rowCount - 1);
 
-    // Run render callback
-    this._renderCallback(this._rowStart, this._rowEnd);
-
-    // Reset debouncer
+    // Reset debouncer (this happens before render callback as the render could trigger it again)
     this._rowStart = undefined;
     this._rowEnd = undefined;
     this._animationFrame = undefined;
+
+    // Run render callback
+    this._renderCallback(start, end);
   }
 }
diff --git a/src/browser/renderer/BaseRenderLayer.ts b/src/browser/renderer/BaseRenderLayer.ts
index 595aa1a52..837f18e42 100644
--- a/src/browser/renderer/BaseRenderLayer.ts
+++ b/src/browser/renderer/BaseRenderLayer.ts
@@ -77,7 +77,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
   public onFocus(): void {}
   public onCursorMove(): void {}
   public onGridChanged(startRow: number, endRow: number): void {}
-  public onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean = false): void {}
+  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {}
 
   public setColors(colorSet: IColorSet): void {
     this._refreshCharAtlas(colorSet);
diff --git a/src/browser/renderer/Renderer.ts b/src/browser/renderer/Renderer.ts
index 0856553f1..5142e4cb4 100644
--- a/src/browser/renderer/Renderer.ts
+++ b/src/browser/renderer/Renderer.ts
@@ -119,7 +119,7 @@ export class Renderer extends Disposable implements IRenderer {
     this._runOperation(l => l.onFocus());
   }
 
-  public onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean = false): void {
+  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {
     this._runOperation(l => l.onSelectionChanged(start, end, columnSelectMode));
   }
 
diff --git a/src/browser/renderer/SelectionRenderLayer.ts b/src/browser/renderer/SelectionRenderLayer.ts
index 257944fcb..5689ce932 100644
--- a/src/browser/renderer/SelectionRenderLayer.ts
+++ b/src/browser/renderer/SelectionRenderLayer.ts
@@ -52,7 +52,7 @@ export class SelectionRenderLayer extends BaseRenderLayer {
     }
   }
 
-  public onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void {
+  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
     // Selection has not changed
     if (!this._didStateChange(start, end, columnSelectMode, this._bufferService.buffer.ydisp)) {
       return;
@@ -110,7 +110,7 @@ export class SelectionRenderLayer extends BaseRenderLayer {
     this._state.ydisp = this._bufferService.buffer.ydisp;
   }
 
-  private _didStateChange(start: [number, number], end: [number, number], columnSelectMode: boolean, ydisp: number): boolean {
+  private _didStateChange(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean, ydisp: number): boolean {
     return !this._areCoordinatesEqual(start, this._state.start) ||
       !this._areCoordinatesEqual(end, this._state.end) ||
       columnSelectMode !== this._state.columnSelectMode ||
diff --git a/src/browser/renderer/Types.d.ts b/src/browser/renderer/Types.d.ts
index 02c62ab2e..cab14b88e 100644
--- a/src/browser/renderer/Types.d.ts
+++ b/src/browser/renderer/Types.d.ts
@@ -49,7 +49,7 @@ export interface IRenderer extends IDisposable {
   onCharSizeChanged(): void;
   onBlur(): void;
   onFocus(): void;
-  onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void;
+  onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
   onCursorMove(): void;
   onOptionsChanged(): void;
   clear(): void;
@@ -104,7 +104,7 @@ export interface IRenderLayer extends IDisposable {
   /**
    * Calls when the selection changes.
    */
-  onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void;
+  onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
 
   /**
    * Registers a handler to join characters to render as a group
diff --git a/src/browser/renderer/dom/DomRenderer.ts b/src/browser/renderer/dom/DomRenderer.ts
index 1303ec1b5..ff9551404 100644
--- a/src/browser/renderer/dom/DomRenderer.ts
+++ b/src/browser/renderer/dom/DomRenderer.ts
@@ -273,7 +273,7 @@ export class DomRenderer extends Disposable implements IRenderer {
     this._rowContainer.classList.add(FOCUS_CLASS);
   }
 
-  public onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void {
+  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
     // Remove all selections
     while (this._selectionContainer.children.length) {
       this._selectionContainer.removeChild(this._selectionContainer.children[0]);
diff --git a/src/browser/services/RenderService.ts b/src/browser/services/RenderService.ts
index 27b66458b..a0ca25d2e 100644
--- a/src/browser/services/RenderService.ts
+++ b/src/browser/services/RenderService.ts
@@ -13,6 +13,12 @@ import { IColorSet } from 'browser/Types';
 import { IOptionsService, IBufferService, ICoreService } from 'common/services/Services';
 import { ICharSizeService, IRenderService } from 'browser/services/Services';
 
+interface ISelectionState {
+  start: [number, number] | undefined;
+  end: [number, number] | undefined;
+  columnSelectMode: boolean;
+}
+
 export class RenderService extends Disposable implements IRenderService {
   public serviceBrand: undefined;
 
@@ -22,8 +28,14 @@ export class RenderService extends Disposable implements IRenderService {
   private _isPaused: boolean = false;
   private _needsFullRefresh: boolean = false;
   private _isNextRenderRedrawOnly: boolean = true;
+  private _needsSelectionRefresh: boolean = false;
   private _canvasWidth: number = 0;
   private _canvasHeight: number = 0;
+  private _selectionState: ISelectionState = {
+    start: undefined,
+    end: undefined,
+    columnSelectMode: false
+  };
 
   private _onDimensionsChange = new EventEmitter<IRenderDimensions>();
   public get onDimensionsChange(): IEvent<IRenderDimensions> { return this._onDimensionsChange.event; }
@@ -91,6 +103,14 @@ export class RenderService extends Disposable implements IRenderService {
 
   private _renderRows(start: number, end: number): void {
     this._renderer.renderRows(start, end);
+
+    // Update selection if needed
+    if (this._needsSelectionRefresh) {
+      this._renderer.onSelectionChanged(this._selectionState.start, this._selectionState.end, this._selectionState.columnSelectMode);
+      this._needsSelectionRefresh = false;
+    }
+
+    // Fire render event only if it was not a redraw
     if (!this._isNextRenderRedrawOnly) {
       this._onRender.fire({ start, end });
     }
@@ -126,7 +146,10 @@ export class RenderService extends Disposable implements IRenderService {
     this._renderer.dispose();
     this._renderer = renderer;
     this._renderer.onRequestRedraw(e => this.refreshRows(e.start, e.end, true));
-    this.refreshRows(0, this._rowCount - 1);
+
+    // Force a refresh
+    this._needsSelectionRefresh = true;
+    this._fullRefresh();
   }
 
   private _fullRefresh(): void {
@@ -165,7 +188,10 @@ export class RenderService extends Disposable implements IRenderService {
     this._renderer.onFocus();
   }
 
-  public onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void {
+  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
+    this._selectionState.start = start;
+    this._selectionState.end = end;
+    this._selectionState.columnSelectMode = columnSelectMode;
     this._renderer.onSelectionChanged(start, end, columnSelectMode);
   }
 
diff --git a/src/browser/services/Services.ts b/src/browser/services/Services.ts
index 28b839852..445cab05f 100644
--- a/src/browser/services/Services.ts
+++ b/src/browser/services/Services.ts
@@ -63,7 +63,7 @@ export interface IRenderService extends IDisposable {
   onCharSizeChanged(): void;
   onBlur(): void;
   onFocus(): void;
-  onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void;
+  onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
   onCursorMove(): void;
   clear(): void;
   registerCharacterJoiner(handler: CharacterJoinerHandler): number;
diff --git a/src/common/InputHandler.ts b/src/common/InputHandler.ts
index 6a7460a48..1ec2a68db 100644
--- a/src/common/InputHandler.ts
+++ b/src/common/InputHandler.ts
@@ -503,7 +503,7 @@ export class InputHandler extends Disposable implements IInputHandler {
     const wraparoundMode = this._coreService.decPrivateModes.wraparound;
     const insertMode = this._coreService.modes.insertMode;
     const curAttr = this._curAttrData;
-    let bufferRow = buffer.lines.get(buffer.y + buffer.ybase)!;
+    let bufferRow = buffer.lines.get(buffer.ybase + buffer.y)!;
 
     this._dirtyRowService.markDirty(buffer.y);
 
@@ -567,10 +567,10 @@ export class InputHandler extends Disposable implements IInputHandler {
             }
             // The line already exists (eg. the initial viewport), mark it as a
             // wrapped line
-            buffer.lines.get(buffer.y)!.isWrapped = true;
+            buffer.lines.get(buffer.ybase + buffer.y)!.isWrapped = true;
           }
           // row changed, get it again
-          bufferRow = buffer.lines.get(buffer.y + buffer.ybase)!;
+          bufferRow = buffer.lines.get(buffer.ybase + buffer.y)!;
         } else {
           buffer.x = cols - 1;
           if (chWidth === 2) {
@@ -1190,7 +1190,7 @@ export class InputHandler extends Disposable implements IInputHandler {
       return;
     }
 
-    const row: number = buffer.y + buffer.ybase;
+    const row: number = buffer.ybase + buffer.y;
 
     const scrollBottomRowsOffset = this._bufferService.rows - 1 - buffer.scrollBottom;
     const scrollBottomAbsolute = this._bufferService.rows - 1 + buffer.ybase - scrollBottomRowsOffset + 1;
@@ -1225,7 +1225,7 @@ export class InputHandler extends Disposable implements IInputHandler {
       return;
     }
 
-    const row: number = buffer.y + buffer.ybase;
+    const row: number = buffer.ybase + buffer.y;
 
     let j: number;
     j = this._bufferService.rows - 1 - buffer.scrollBottom;
@@ -1254,7 +1254,7 @@ export class InputHandler extends Disposable implements IInputHandler {
    */
   public insertChars(params: IParams): void {
     this._restrictCursor();
-    const line = this._bufferService.buffer.lines.get(this._bufferService.buffer.y + this._bufferService.buffer.ybase);
+    const line = this._bufferService.buffer.lines.get(this._bufferService.buffer.ybase + this._bufferService.buffer.y);
     if (line) {
       line.insertCells(
         this._bufferService.buffer.x,
@@ -1279,7 +1279,7 @@ export class InputHandler extends Disposable implements IInputHandler {
    */
   public deleteChars(params: IParams): void {
     this._restrictCursor();
-    const line = this._bufferService.buffer.lines.get(this._bufferService.buffer.y + this._bufferService.buffer.ybase);
+    const line = this._bufferService.buffer.lines.get(this._bufferService.buffer.ybase + this._bufferService.buffer.y);
     if (line) {
       line.deleteCells(
         this._bufferService.buffer.x,
@@ -1451,7 +1451,7 @@ export class InputHandler extends Disposable implements IInputHandler {
    */
   public eraseChars(params: IParams): void {
     this._restrictCursor();
-    const line = this._bufferService.buffer.lines.get(this._bufferService.buffer.y + this._bufferService.buffer.ybase);
+    const line = this._bufferService.buffer.lines.get(this._bufferService.buffer.ybase + this._bufferService.buffer.y);
     if (line) {
       line.replaceCells(
         this._bufferService.buffer.x,
@@ -2720,8 +2720,8 @@ export class InputHandler extends Disposable implements IInputHandler {
       // test: echo -ne '\e[1;1H\e[44m\eM\e[0m'
       // blankLine(true) is xterm/linux behavior
       const scrollRegionHeight = buffer.scrollBottom - buffer.scrollTop;
-      buffer.lines.shiftElements(buffer.y + buffer.ybase, scrollRegionHeight, 1);
-      buffer.lines.set(buffer.y + buffer.ybase, buffer.getBlankLine(this._eraseAttrData()));
+      buffer.lines.shiftElements(buffer.ybase + buffer.y, scrollRegionHeight, 1);
+      buffer.lines.set(buffer.ybase + buffer.y, buffer.getBlankLine(this._eraseAttrData()));
       this._dirtyRowService.markRangeDirty(buffer.scrollTop, buffer.scrollBottom);
     } else {
       buffer.y--;
@@ -2786,7 +2786,7 @@ export class InputHandler extends Disposable implements IInputHandler {
 
     this._setCursor(0, 0);
     for (let yOffset = 0; yOffset < this._bufferService.rows; ++yOffset) {
-      const row = buffer.y + buffer.ybase + yOffset;
+      const row = buffer.ybase + buffer.y + yOffset;
       const line = buffer.lines.get(row);
       if (line) {
         line.fill(cell);