Fixes #99313

src/vs/code/electron-main/app.ts

@@ -85,6 +85,7 @@ import { ActiveWindowManager } from 'vs/platform/windows/common/windowTracker';
 import { IKeyboardLayoutMainService, KeyboardLayoutMainService } from 'vs/platform/keyboardLayout/electron-main/keyboardLayoutMainService';
 import { toErrorMessage } from 'vs/base/common/errorMessage';
 import { NativeParsedArgs } from 'vs/platform/environment/common/argv';
+import { DisplayMainService, IDisplayMainService } from 'vs/platform/display/electron-main/displayMainService';
 
 export class CodeApplication extends Disposable {
 	private windowsMainService: IWindowsMainService | undefined;
@@ -464,6 +465,7 @@ export class CodeApplication extends Disposable {
 		services.set(IIssueMainService, new SyncDescriptor(IssueMainService, [machineId, this.userEnv]));
 		services.set(IEncryptionMainService, new SyncDescriptor(EncryptionMainService, [machineId]));
 		services.set(IKeyboardLayoutMainService, new SyncDescriptor(KeyboardLayoutMainService));
+		services.set(IDisplayMainService, new SyncDescriptor(DisplayMainService));
 		services.set(INativeHostMainService, new SyncDescriptor(NativeHostMainService));
 		services.set(IWebviewManagerService, new SyncDescriptor(WebviewMainService));
 		services.set(IWorkspacesService, new SyncDescriptor(WorkspacesService));
@@ -558,6 +560,10 @@ export class CodeApplication extends Disposable {
 		const keyboardLayoutChannel = createChannelReceiver(keyboardLayoutMainService);
 		electronIpcServer.registerChannel('keyboardLayout', keyboardLayoutChannel);
 
+		const displayMainService = accessor.get(IDisplayMainService);
+		const displayChannel = createChannelReceiver(displayMainService);
+		electronIpcServer.registerChannel('display', displayChannel);
+
 		const nativeHostMainService = this.nativeHostMainService = accessor.get(INativeHostMainService);
 		const nativeHostChannel = createChannelReceiver(this.nativeHostMainService);
 		electronIpcServer.registerChannel('nativeHost', nativeHostChannel);

src/vs/code/electron-main/window.ts

@@ -468,9 +468,6 @@ export class CodeWindow extends Disposable implements ICodeWindow {
 					return; // disposed
 				}
 
-				// Notify renderers about displays changed
-				this.sendWhenReady('vscode:displayChanged');
-
 				// Simple fullscreen doesn't resize automatically when the resolution changes so as a workaround
 				// we need to detect when display metrics change or displays are added/removed and toggle the
 				// fullscreen manually.

src/vs/platform/display/common/displayMainService.ts

+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { Event } from 'vs/base/common/event';
+
+export interface IDisplayMainService {
+	readonly _serviceBrand: undefined;
+	readonly onDidDisplayChanged: Event<void>;
+}

src/vs/platform/display/electron-main/displayMainService.ts

+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { createDecorator } from 'vs/platform/instantiation/common/instantiation';
+import { IDisplayMainService as ICommonDisplayMainService } from 'vs/platform/display/common/displayMainService';
+import { Emitter } from 'vs/base/common/event';
+import { Disposable, toDisposable } from 'vs/base/common/lifecycle';
+import { app, Display, screen } from 'electron';
+import { RunOnceScheduler } from 'vs/base/common/async';
+
+export const IDisplayMainService = createDecorator<IDisplayMainService>('displayMainService');
+
+export interface IDisplayMainService extends ICommonDisplayMainService { }
+
+export class DisplayMainService extends Disposable implements ICommonDisplayMainService {
+
+	declare readonly _serviceBrand: undefined;
+
+	private readonly _onDidDisplayChanged = this._register(new Emitter<void>());
+	readonly onDidDisplayChanged = this._onDidDisplayChanged.event;
+
+	constructor() {
+		super();
+
+		const displayChangedScheduler = this._register(new RunOnceScheduler(() => {
+			this._onDidDisplayChanged.fire();
+		}, 100));
+
+		app.whenReady().then(() => {
+
+			const displayChangedListener = (event: Event, display: Display, changedMetrics?: string[]) => {
+				displayChangedScheduler.schedule();
+			};
+
+			screen.on('display-metrics-changed', displayChangedListener);
+			this._register(toDisposable(() => screen.removeListener('display-metrics-changed', displayChangedListener)));
+
+			screen.on('display-added', displayChangedListener);
+			this._register(toDisposable(() => screen.removeListener('display-added', displayChangedListener)));
+
+			screen.on('display-removed', displayChangedListener);
+			this._register(toDisposable(() => screen.removeListener('display-removed', displayChangedListener)));
+		});
+	}
+}

src/vs/workbench/contrib/codeEditor/electron-sandbox/codeEditor.contribution.ts

@@ -3,6 +3,7 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
+import './displayChangeRemeasureFonts';
 import './inputClipboardActions';
 import './selectionClipboard';
 import './sleepResumeRepaintMinimap';

src/vs/workbench/contrib/codeEditor/electron-sandbox/displayChangeRemeasureFonts.ts

+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { LifecyclePhase } from 'vs/workbench/services/lifecycle/common/lifecycle';
+import { Registry } from 'vs/platform/registry/common/platform';
+import { Extensions as WorkbenchExtensions, IWorkbenchContribution, IWorkbenchContributionsRegistry } from 'vs/workbench/common/contributions';
+import { Disposable } from 'vs/base/common/lifecycle';
+import { IMainProcessService } from 'vs/platform/ipc/electron-sandbox/mainProcessService';
+import { IDisplayMainService } from 'vs/platform/display/common/displayMainService';
+import { createChannelSender } from 'vs/base/parts/ipc/common/ipc';
+import { clearAllFontInfos } from 'vs/editor/browser/config/configuration';
+
+class DisplayChangeRemeasureFonts extends Disposable implements IWorkbenchContribution {
+
+	constructor(
+		@IMainProcessService mainProcessService: IMainProcessService
+	) {
+		super();
+		const displayMainService = createChannelSender<IDisplayMainService>(mainProcessService.getChannel('display'));
+		displayMainService.onDidDisplayChanged(() => {
+			clearAllFontInfos();
+		});
+	}
+}
+
+Registry.as<IWorkbenchContributionsRegistry>(WorkbenchExtensions.Workbench).registerWorkbenchContribution(DisplayChangeRemeasureFonts, LifecyclePhase.Eventually);

src/vs/workbench/electron-sandbox/window.ts

@@ -59,7 +59,6 @@ import { IHostService } from 'vs/workbench/services/host/browser/host';
 import { IWorkingCopyService, WorkingCopyCapabilities } from 'vs/workbench/services/workingCopy/common/workingCopyService';
 import { AutoSaveMode, IFilesConfigurationService } from 'vs/workbench/services/filesConfiguration/common/filesConfigurationService';
 import { Event } from 'vs/base/common/event';
-import { clearAllFontInfos } from 'vs/editor/browser/config/configuration';
 import { IRemoteAuthorityResolverService } from 'vs/platform/remote/common/remoteAuthorityResolver';
 import { IAddressProvider, IAddress } from 'vs/platform/remote/common/remoteAgentConnection';
 import { IEditorGroupsService } from 'vs/workbench/services/editor/common/editorGroupsService';
@@ -205,11 +204,6 @@ export class NativeWindow extends Disposable {
 			choices
 		));
 
-		// Display change events
-		ipcRenderer.on('vscode:displayChanged', () => {
-			clearAllFontInfos();
-		});
-
 		// Fullscreen Events
 		ipcRenderer.on('vscode:enterFullScreen', async () => {
 			await this.lifecycleService.when(LifecyclePhase.Ready);