diff --git a/src/vs/workbench/api/browser/mainThreadComments.ts b/src/vs/workbench/api/browser/mainThreadComments.ts
index 79dbfca1f18..fad1a18c266 100644
--- a/src/vs/workbench/api/browser/mainThreadComments.ts
+++ b/src/vs/workbench/api/browser/mainThreadComments.ts
@@ -6,7 +6,6 @@
 import { CancellationToken } from 'vs/base/common/cancellation';
 import { Emitter, Event } from 'vs/base/common/event';
 import { Disposable, DisposableStore, dispose, IDisposable } from 'vs/base/common/lifecycle';
-import { keys } from 'vs/base/common/map';
 import { URI, UriComponents } from 'vs/base/common/uri';
 import { generateUuid } from 'vs/base/common/uuid';
 import { IRange } from 'vs/editor/common/core/range';
@@ -284,7 +283,7 @@ export class MainThreadCommentController {
 
 	async getDocumentComments(resource: URI, token: CancellationToken) {
 		let ret: modes.CommentThread[] = [];
-		for (let thread of keys(this._threads)) {
+		for (let thread of [...this._threads.keys()]) {
 			const commentThread = this._threads.get(thread)!;
 			if (commentThread.resource === resource.toString()) {
 				ret.push(commentThread);
@@ -315,7 +314,7 @@ export class MainThreadCommentController {
 
 	getAllComments(): MainThreadCommentThread[] {
 		let ret: MainThreadCommentThread[] = [];
-		for (let thread of keys(this._threads)) {
+		for (let thread of [...this._threads.keys()]) {
 			ret.push(this._threads.get(thread)!);
 		}
 
@@ -486,7 +485,7 @@ export class MainThreadComments extends Disposable implements MainThreadComments
 		if (!commentsPanelAlreadyConstructed && !this._openViewListener) {
 			this._openViewListener = this._viewsService.onDidChangeViewVisibility(e => {
 				if (e.id === COMMENTS_VIEW_ID && e.visible) {
-					keys(this._commentControllers).forEach(handle => {
+					[...this._commentControllers.keys()].forEach(handle => {
 						let threads = this._commentControllers.get(handle)!.getAllComments();
 
 						if (threads.length) {