Mark before and after cursor rows dirty when changed

The DOM renderer renders the cursor as part of the content, not on a
separate layer, so it needs to be marked dirty to draw.

Fixes #2581

src/InputHandler.ts

@@ -546,6 +546,7 @@ export class InputHandler extends Disposable implements IInputHandler {
     // make buffer local for faster access
     const buffer = this._bufferService.buffer;
 
+    this._dirtyRowService.markDirty(buffer.y);
     if (this._optionsService.options.convertEol) {
       buffer.x = 0;
     }
@@ -560,6 +561,7 @@ export class InputHandler extends Disposable implements IInputHandler {
     if (buffer.x >= this._bufferService.cols) {
       buffer.x--;
     }
+    this._dirtyRowService.markDirty(buffer.y);
 
     this._onLineFeed.fire();
   }
@@ -624,12 +626,14 @@ export class InputHandler extends Disposable implements IInputHandler {
     this._bufferService.buffer.y = this._terminal.originMode
       ? Math.min(this._bufferService.buffer.scrollBottom, Math.max(this._bufferService.buffer.scrollTop, this._bufferService.buffer.y))
       : Math.min(this._bufferService.rows - 1, Math.max(0, this._bufferService.buffer.y));
+    this._dirtyRowService.markDirty(this._bufferService.buffer.y);
   }
 
   /**
    * Set absolute cursor position.
    */
   private _setCursor(x: number, y: number): void {
+    this._dirtyRowService.markDirty(this._bufferService.buffer.y);
     if (this._terminal.originMode) {
       this._bufferService.buffer.x = x;
       this._bufferService.buffer.y = this._bufferService.buffer.scrollTop + y;
@@ -638,6 +642,7 @@ export class InputHandler extends Disposable implements IInputHandler {
       this._bufferService.buffer.y = y;
     }
     this._restrictCursor();
+    this._dirtyRowService.markDirty(this._bufferService.buffer.y);
   }
 
   /**