src/vs/workbench/contrib/comments/browser/commentThreadZoneWidget.ts/ReviewZoneWidget/onEditorMouseUp
class ReviewZoneWidget:	private onEditorMouseUp(e: IEditorMouseEvent): void {
		const matchedLineNumber = isMouseUpEventMatchMouseDown(this.mouseDownInfo, e);
		this.mouseDownInfo = null;

		if (matchedLineNumber === null || !e.target.element) {
			return;
		}

		if (this._commentGlyph && this._commentGlyph.getPosition().position!.lineNumber !== matchedLineNumber) {
			return;
		}

		if (e.target.element.className.indexOf('comment-thread') >= 0) {
			this.toggleExpand(matchedLineNumber);
		}
	}