diff --git a/src/vs/workbench/api/browser/mainThreadComments.ts b/src/vs/workbench/api/browser/mainThreadComments.ts
index 55965f6e58c..43bcbaa54e0 100644
--- a/src/vs/workbench/api/browser/mainThreadComments.ts
+++ b/src/vs/workbench/api/browser/mainThreadComments.ts
@@ -3,7 +3,7 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import { Disposable, IDisposable, dispose } from 'vs/base/common/lifecycle';
+import { Disposable, IDisposable, dispose, DisposableStore } from 'vs/base/common/lifecycle';
 import { ICodeEditor, isCodeEditor, isDiffEditor, IDiffEditor } from 'vs/editor/browser/editorBrowser';
 import * as modes from 'vs/editor/common/modes';
 import { extHostNamedCustomer } from 'vs/workbench/api/common/extHostCustomers';
@@ -473,10 +473,12 @@ export class MainThreadComments extends Disposable implements MainThreadComments
 	private _commentControllers = new Map<number, MainThreadCommentController>();
 
 	private _activeCommentThread?: MainThreadCommentThread;
+	private readonly _activeCommentThreadDisposables = this._register(new DisposableStore());
 	private _input?: modes.CommentInput;
 
 	private _openPanelListener: IDisposable | null;
 
+
 	constructor(
 		extHostContext: IExtHostContext,
 		@IEditorService private readonly _editorService: IEditorService,
@@ -488,7 +490,7 @@ export class MainThreadComments extends Disposable implements MainThreadComments
 		super();
 		this._proxy = extHostContext.getProxy(ExtHostContext.ExtHostComments);
 
-		this._disposables.push(this._commentService.onDidChangeActiveCommentThread(async thread => {
+		this._register(this._commentService.onDidChangeActiveCommentThread(async thread => {
 			let handle = (thread as MainThreadCommentThread).controllerHandle;
 			let controller = this._commentControllers.get(handle);
 
@@ -496,11 +498,11 @@ export class MainThreadComments extends Disposable implements MainThreadComments
 				return;
 			}
 
-			this._activeCommentThreadDisposables = dispose(this._activeCommentThreadDisposables);
+			this._activeCommentThreadDisposables.clear();
 			this._activeCommentThread = thread as MainThreadCommentThread;
 			controller.activeCommentThread = this._activeCommentThread;
 
-			this._activeCommentThreadDisposables.push(this._activeCommentThread.onDidChangeInput(input => { // todo, dispose
+			this._activeCommentThreadDisposables.add(this._activeCommentThread.onDidChangeInput(input => { // todo, dispose
 				this._input = input;
 				this._proxy.$onCommentWidgetInputChange(handle, URI.parse(this._activeCommentThread!.resource), this._activeCommentThread!.range, this._input ? this._input.value : undefined);
 			}));