fixes #99798

cc @roblourens for changes in settings

src/vs/base/browser/ui/list/listWidget.ts

@@ -854,6 +854,7 @@ export interface IListOptions<T> {
 	readonly horizontalScrolling?: boolean;
 	readonly additionalScrollHeight?: number;
 	readonly transformOptimization?: boolean;
+	readonly smoothScrolling?: boolean;
 }
 
 export interface IListStyles {

src/vs/platform/list/browser/listService.ts

@@ -179,6 +179,8 @@ function toWorkbenchListOptions<T>(options: IListOptions<T>, configurationServic
 		}
 	};
 
+	result.smoothScrolling = configurationService.getValue<boolean>(listSmoothScrolling);
+
 	return [result, disposables];
 }
 
@@ -193,7 +195,6 @@ export interface IWorkbenchListOptions<T> extends IWorkbenchListOptionsUpdate, I
 export class WorkbenchList<T> extends List<T> {
 
 	readonly contextKeyService: IContextKeyService;
-	private readonly configurationService: IConfigurationService;
 	private readonly themeService: IThemeService;
 
 	private listHasSelectionOrFocus: IContextKey<boolean>;
@@ -231,7 +232,6 @@ export class WorkbenchList<T> extends List<T> {
 		this.disposables.add(workbenchListOptionsDisposable);
 
 		this.contextKeyService = createScopedContextKeyService(contextKeyService, this);
-		this.configurationService = configurationService;
 		this.themeService = themeService;
 
 		const listSupportsMultiSelect = WorkbenchListSupportsMultiSelectContextKey.bindTo(this.contextKeyService);
@@ -265,8 +265,25 @@ export class WorkbenchList<T> extends List<T> {
 
 			this.listHasSelectionOrFocus.set(selection.length > 0 || focus.length > 0);
 		}));
+		this.disposables.add(configurationService.onDidChangeConfiguration(e => {
+			if (e.affectsConfiguration(multiSelectModifierSettingKey)) {
+				this._useAltAsMultipleSelectionModifier = useAltAsMultipleSelectionModifier(configurationService);
+			}
 
-		this.registerListeners();
+			let options: IListOptionsUpdate = {};
+
+			if (e.affectsConfiguration(horizontalScrollingKey) && this.horizontalScrolling === undefined) {
+				const horizontalScrolling = configurationService.getValue<boolean>(horizontalScrollingKey);
+				options = { ...options, horizontalScrolling };
+			}
+			if (e.affectsConfiguration(listSmoothScrolling)) {
+				const smoothScrolling = configurationService.getValue<boolean>(listSmoothScrolling);
+				options = { ...options, smoothScrolling };
+			}
+			if (Object.keys(options).length > 0) {
+				this.updateOptions(options);
+			}
+		}));
 	}
 
 	updateOptions(options: IWorkbenchListOptionsUpdate): void {
@@ -292,18 +309,6 @@ export class WorkbenchList<T> extends List<T> {
 		this._styler = attachListStyler(this, this.themeService, styles);
 	}
 
-	private registerListeners(): void {
-		this.disposables.add(this.configurationService.onDidChangeConfiguration(e => {
-			if (e.affectsConfiguration(multiSelectModifierSettingKey)) {
-				this._useAltAsMultipleSelectionModifier = useAltAsMultipleSelectionModifier(this.configurationService);
-			}
-			if (e.affectsConfiguration(horizontalScrollingKey) && this.horizontalScrolling === undefined) {
-				const horizontalScrolling = this.configurationService.getValue<boolean>(horizontalScrollingKey);
-				this.updateOptions({ horizontalScrolling });
-			}
-		}));
-	}
-
 	get useAltAsMultipleSelectionModifier(): boolean {
 		return this._useAltAsMultipleSelectionModifier;
 	}
@@ -316,7 +321,6 @@ export interface IWorkbenchPagedListOptions<T> extends IWorkbenchListOptionsUpda
 export class WorkbenchPagedList<T> extends PagedList<T> {
 
 	readonly contextKeyService: IContextKeyService;
-	private readonly configurationService: IConfigurationService;
 
 	private readonly disposables: DisposableStore;
 
@@ -350,7 +354,6 @@ export class WorkbenchPagedList<T> extends PagedList<T> {
 		this.disposables.add(workbenchListOptionsDisposable);
 
 		this.contextKeyService = createScopedContextKeyService(contextKeyService, this);
-		this.configurationService = configurationService;
 		this.horizontalScrolling = options.horizontalScrolling;
 
 		const listSupportsMultiSelect = WorkbenchListSupportsMultiSelectContextKey.bindTo(this.contextKeyService);
@@ -365,17 +368,23 @@ export class WorkbenchPagedList<T> extends PagedList<T> {
 			this.disposables.add(attachListStyler(this, themeService, options.overrideStyles));
 		}
 
-		this.registerListeners();
-	}
-
-	private registerListeners(): void {
-		this.disposables.add(this.configurationService.onDidChangeConfiguration(e => {
+		this.disposables.add(configurationService.onDidChangeConfiguration(e => {
 			if (e.affectsConfiguration(multiSelectModifierSettingKey)) {
-				this._useAltAsMultipleSelectionModifier = useAltAsMultipleSelectionModifier(this.configurationService);
+				this._useAltAsMultipleSelectionModifier = useAltAsMultipleSelectionModifier(configurationService);
 			}
+
+			let options: IListOptionsUpdate = {};
+
 			if (e.affectsConfiguration(horizontalScrollingKey) && this.horizontalScrolling === undefined) {
-				const horizontalScrolling = this.configurationService.getValue<boolean>(horizontalScrollingKey);
-				this.updateOptions({ horizontalScrolling });
+				const horizontalScrolling = configurationService.getValue<boolean>(horizontalScrollingKey);
+				options = { ...options, horizontalScrolling };
+			}
+			if (e.affectsConfiguration(listSmoothScrolling)) {
+				const smoothScrolling = configurationService.getValue<boolean>(listSmoothScrolling);
+				options = { ...options, smoothScrolling };
+			}
+			if (Object.keys(options).length > 0) {
+				this.updateOptions(options);
 			}
 		}));
 	}

src/vs/workbench/contrib/preferences/browser/settingsTree.ts

@@ -1845,6 +1845,7 @@ export class SettingsTree extends ObjectTree<SettingsTreeElement> {
 		viewState: ISettingsEditorViewState,
 		renderers: ITreeRenderer<any, void, any>[],
 		@IThemeService themeService: IThemeService,
+		@IConfigurationService configurationService: IConfigurationService,
 		@IInstantiationService instantiationService: IInstantiationService,
 	) {
 		super('SettingsTree', container,
@@ -1870,7 +1871,8 @@ export class SettingsTree extends ObjectTree<SettingsTreeElement> {
 					}
 				},
 				styleController: id => new DefaultStyleController(DOM.createStyleSheet(container), id),
-				filter: instantiationService.createInstance(SettingsTreeFilter, viewState)
+				filter: instantiationService.createInstance(SettingsTreeFilter, viewState),
+				smoothScrolling: configurationService.getValue<boolean>('workbench.list.smoothScrolling'),
 			});
 
 		this.disposables.clear();
@@ -1945,6 +1947,14 @@ export class SettingsTree extends ObjectTree<SettingsTreeElement> {
 		}, colors => {
 			this.style(colors);
 		}));
+
+		this.disposables.add(configurationService.onDidChangeConfiguration(e => {
+			if (e.affectsConfiguration('workbench.list.smoothScrolling')) {
+				this.updateOptions({
+					smoothScrolling: configurationService.getValue<boolean>('workbench.list.smoothScrolling')
+				});
+			}
+		}));
 	}
 
 	protected createModel(user: string, view: IList<ITreeNode<SettingsTreeGroupChild>>, options: IObjectTreeOptions<SettingsTreeGroupChild>): ITreeModel<SettingsTreeGroupChild | null, void, SettingsTreeGroupChild | null> {