From 2d0b88e904c65c8e4f066bd357440dd4aa146adc Mon Sep 17 00:00:00 2001
From: Rob Lourens <roblourens@gmail.com>
Date: Fri, 13 Feb 2026 23:58:21 +0000
Subject: [PATCH] Remember chat editor scroll position when switching tabs
 (#295278)

---
 .../contrib/chat/browser/widget/chatWidget.ts |  8 ++++
 .../browser/widgetHosts/editor/chatEditor.ts  | 44 ++++++++++++++++---
 2 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts b/src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts
index 32024aabc22..bc7df9a2613 100644
--- a/src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts
+++ b/src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts
@@ -634,6 +634,14 @@ export class ChatWidget extends Disposable implements IChatWidget {
 		return this.input.height.get() + this.listWidget.contentHeight + this.chatSuggestNextWidget.height;
 	}
 
+	get scrollTop(): number {
+		return this.listWidget.scrollTop;
+	}
+
+	set scrollTop(value: number) {
+		this.listWidget.scrollTop = value;
+	}
+
 	get attachmentModel(): ChatAttachmentModel {
 		return this.input.attachmentModel;
 	}
diff --git a/src/vs/workbench/contrib/chat/browser/widgetHosts/editor/chatEditor.ts b/src/vs/workbench/contrib/chat/browser/widgetHosts/editor/chatEditor.ts
index fffb5a27aa8..8a1c71fb615 100644
--- a/src/vs/workbench/contrib/chat/browser/widgetHosts/editor/chatEditor.ts
+++ b/src/vs/workbench/contrib/chat/browser/widgetHosts/editor/chatEditor.ts
@@ -9,7 +9,9 @@ import { raceCancellationError } from '../../../../../../base/common/async.js';
 import { CancellationToken } from '../../../../../../base/common/cancellation.js';
 import { Codicon } from '../../../../../../base/common/codicons.js';
 import { ThemeIcon } from '../../../../../../base/common/themables.js';
+import { URI } from '../../../../../../base/common/uri.js';
 import * as nls from '../../../../../../nls.js';
+import { ITextResourceConfigurationService } from '../../../../../../editor/common/services/textResourceConfiguration.js';
 import { IContextKeyService, IScopedContextKeyService } from '../../../../../../platform/contextkey/common/contextkey.js';
 import { IEditorOptions } from '../../../../../../platform/editor/common/editor.js';
 import { IInstantiationService } from '../../../../../../platform/instantiation/common/instantiation.js';
@@ -18,10 +20,12 @@ import { IStorageService } from '../../../../../../platform/storage/common/stora
 import { ITelemetryService } from '../../../../../../platform/telemetry/common/telemetry.js';
 import { editorBackground, editorForeground, inputBackground } from '../../../../../../platform/theme/common/colorRegistry.js';
 import { IThemeService } from '../../../../../../platform/theme/common/themeService.js';
-import { EditorPane } from '../../../../../browser/parts/editor/editorPane.js';
+import { AbstractEditorWithViewState } from '../../../../../browser/parts/editor/editorWithViewState.js';
 import { IEditorOpenContext } from '../../../../../common/editor.js';
+import { EditorInput } from '../../../../../common/editor/editorInput.js';
 import { EDITOR_DRAG_AND_DROP_BACKGROUND } from '../../../../../common/theme.js';
-import { IEditorGroup } from '../../../../../services/editor/common/editorGroupsService.js';
+import { IEditorGroup, IEditorGroupsService } from '../../../../../services/editor/common/editorGroupsService.js';
+import { IEditorService } from '../../../../../services/editor/common/editorService.js';
 import { ChatContextKeys } from '../../../common/actions/chatContextKeys.js';
 import { IChatModel, IChatModelInputState, IExportableChatData, ISerializableChatData } from '../../../common/model/chatModel.js';
 import { IChatService } from '../../../common/chatService/chatService.js';
@@ -45,7 +49,13 @@ export interface IChatEditorOptions extends IEditorOptions {
 	};
 }
 
-export class ChatEditor extends EditorPane {
+export interface IChatEditorViewState {
+	scrollTop: number;
+}
+
+export class ChatEditor extends AbstractEditorWithViewState<IChatEditorViewState> {
+	private static readonly VIEW_STATE_KEY = 'chatEditorViewState';
+
 	private _widget!: ChatWidget;
 	public get widget(): ChatWidget {
 		return this._widget;
@@ -63,13 +73,16 @@ export class ChatEditor extends EditorPane {
 		group: IEditorGroup,
 		@ITelemetryService telemetryService: ITelemetryService,
 		@IThemeService themeService: IThemeService,
-		@IInstantiationService private readonly instantiationService: IInstantiationService,
+		@IInstantiationService instantiationService: IInstantiationService,
 		@IStorageService storageService: IStorageService,
 		@IChatSessionsService private readonly chatSessionsService: IChatSessionsService,
 		@IContextKeyService private readonly contextKeyService: IContextKeyService,
 		@IChatService private readonly chatService: IChatService,
+		@ITextResourceConfigurationService textResourceConfigurationService: ITextResourceConfigurationService,
+		@IEditorService editorService: IEditorService,
+		@IEditorGroupsService editorGroupService: IEditorGroupsService,
 	) {
-		super(ChatEditorInput.EditorID, group, telemetryService, themeService, storageService);
+		super(ChatEditorInput.EditorID, group, ChatEditor.VIEW_STATE_KEY, telemetryService, instantiationService, storageService, textResourceConfigurationService, themeService, editorService, editorGroupService);
 	}
 
 	private async clear() {
@@ -138,7 +151,6 @@ export class ChatEditor extends EditorPane {
 	}
 
 	override clearInput(): void {
-		this.saveState();
 		this.widget.setModel(undefined);
 		super.clearInput();
 	}
@@ -242,6 +254,11 @@ export class ChatEditor extends EditorPane {
 
 			this.updateModel(editorModel.model);
 
+			const viewState = this.loadEditorViewState(input, context);
+			if (viewState) {
+				this._widget.scrollTop = viewState.scrollTop;
+			}
+
 			if (isContributedChatSession && options?.title?.preferred && input.sessionResource) {
 				this.chatService.setChatSessionTitle(input.sessionResource, options.title.preferred);
 			}
@@ -255,6 +272,21 @@ export class ChatEditor extends EditorPane {
 		this.widget.setModel(model);
 	}
 
+	protected computeEditorViewState(_resource: URI): IChatEditorViewState | undefined {
+		if (!this._widget) {
+			return undefined;
+		}
+		return { scrollTop: this._widget.scrollTop };
+	}
+
+	protected tracksEditorViewState(input: EditorInput): boolean {
+		return input instanceof ChatEditorInput;
+	}
+
+	protected toEditorViewStateResource(input: EditorInput): URI | undefined {
+		return (input as ChatEditorInput).sessionResource;
+	}
+
 	override layout(dimension: dom.Dimension, position?: dom.IDomPosition | undefined): void {
 		this.dimension = dimension;
 		if (this.widget) {