src/vs/workbench/api/browser/mainThreadEditorTabs.ts/MainThreadEditorTabs/_subscribeToGroup
class MainThreadEditorTabs:	private _subscribeToGroup(group: IEditorGroup) {
		this._groups.get(group)?.dispose();
		const listener = group.onDidGroupChange(e => {
			if (MainThreadEditorTabs._GroupEventFilter.has(e.kind)) {
				this._pushEditorTabs();
			}
		});
		this._groups.set(group, listener);
	}