fixes #67188

src/vs/editor/contrib/referenceSearch/referencesTree.ts

@@ -20,7 +20,7 @@ import { escape } from 'vs/base/common/strings';
 import { Disposable } from 'vs/base/common/lifecycle';
 import { IInstantiationService } from 'vs/platform/instantiation/common/instantiation';
 import { IAccessibilityProvider } from 'vs/base/browser/ui/list/listWidget';
-import { IListVirtualDelegate, IKeyboardNavigationLabelProvider } from 'vs/base/browser/ui/list/list';
+import { IListVirtualDelegate, IKeyboardNavigationLabelProvider, IIdentityProvider } from 'vs/base/browser/ui/list/list';
 import { IKeyboardEvent } from 'vs/base/browser/keyboardEvent';
 import { IKeybindingService } from 'vs/platform/keybinding/common/keybinding';
 import { basename } from 'vs/base/common/paths';
@@ -93,6 +93,13 @@ export class StringRepresentationProvider implements IKeyboardNavigationLabelPro
 	}
 }
 
+export class IdentityProvider implements IIdentityProvider<TreeElement> {
+
+	getId(element: TreeElement): { toString(): string; } {
+		return element.id;
+	}
+}
+
 //#region render: File
 
 class FileReferencesTemplate extends Disposable {

src/vs/editor/contrib/referenceSearch/referencesWidget.ts

@@ -21,7 +21,7 @@ import { IModelDeltaDecoration, TrackedRangeStickiness } from 'vs/editor/common/
 import { ModelDecorationOptions, TextModel } from 'vs/editor/common/model/textModel';
 import { Location } from 'vs/editor/common/modes';
 import { ITextEditorModel, ITextModelService } from 'vs/editor/common/services/resolverService';
-import { AriaProvider, DataSource, Delegate, FileReferencesRenderer, OneReferenceRenderer, TreeElement, StringRepresentationProvider } from 'vs/editor/contrib/referenceSearch/referencesTree';
+import { AriaProvider, DataSource, Delegate, FileReferencesRenderer, OneReferenceRenderer, TreeElement, StringRepresentationProvider, IdentityProvider } from 'vs/editor/contrib/referenceSearch/referencesTree';
 import * as nls from 'vs/nls';
 import { RawContextKey } from 'vs/platform/contextkey/common/contextkey';
 import { IInstantiationService } from 'vs/platform/instantiation/common/instantiation';
@@ -358,11 +358,12 @@ export class ReferenceWidget extends PeekViewWidget {
 			this._instantiationService.createInstance(OneReferenceRenderer),
 		];
 
-		const treeOptions = {
+		const treeOptions: IAsyncDataTreeOptions<TreeElement> = {
 			ariaLabel: nls.localize('treeAriaLabel', "References"),
 			keyboardSupport: this._defaultTreeKeyboardSupport,
 			accessibilityProvider: new AriaProvider(),
-			keyboardNavigationLabelProvider: this._instantiationService.createInstance(StringRepresentationProvider)
+			keyboardNavigationLabelProvider: this._instantiationService.createInstance(StringRepresentationProvider),
+			identityProvider: new IdentityProvider()
 		};
 
 		const treeDataSource = this._instantiationService.createInstance(DataSource);