better regexp, fix offset issue in #4294

src/browser/renderer/dom/DomRendererRowFactory.ts

@@ -49,7 +49,7 @@ export class DomRendererRowFactory {
     this._columnSelectMode = columnSelectMode;
   }
 
-  public createRow(lineData: IBufferLine, row: number, isCursorRow: boolean, cursorStyle: string | undefined, cursorX: number, cursorBlink: boolean, cellWidth: number, cols: number, cellMap: Uint16Array): DocumentFragment {
+  public createRow(lineData: IBufferLine, row: number, isCursorRow: boolean, cursorStyle: string | undefined, cursorX: number, cursorBlink: boolean, cellWidth: number, cols: number, cellMap: Int16Array): DocumentFragment {
     // NOTE: `cellMap` maps cell positions to a span element index in a row.
     // All positions should be updated, even skipped ones after wide chars or left overs at the end,
     // otherwise the mouse hover logic might mark the wrong elements as underlined.
@@ -316,7 +316,7 @@ export class DomRendererRowFactory {
     // since the loop above might exit early not handling all cells,
     // also set remaining cell positions to last element index
     if (x < cols - 1) {
-      cellMap.subarray(x + 1).fill(elemIndex);
+      cellMap.subarray(x).fill(++elemIndex);
     }
 
     return fragment;