src/vs/workbench/api/browser/mainThreadNotebookEditors.ts/MainThreadNotebookEditors/constructor
class MainThreadNotebookEditors:	constructor(
		extHostContext: IExtHostContext,
		@IEditorService private readonly _editorService: IEditorService,
		@ILogService private readonly _logService: ILogService,
		@INotebookEditorService private readonly _notebookEditorService: INotebookEditorService,
		@IEditorGroupsService private readonly _editorGroupService: IEditorGroupsService
	) {
		this._proxy = extHostContext.getProxy(ExtHostContext.ExtHostNotebookEditors);

		this._editorService.onDidActiveEditorChange(() => this._updateEditorViewColumns(), this, this._disposables);
		this._editorGroupService.onDidRemoveGroup(() => this._updateEditorViewColumns(), this, this._disposables);
		this._editorGroupService.onDidMoveGroup(() => this._updateEditorViewColumns(), this, this._disposables);
	}