diff --git a/extensions/typescript-language-features/src/typescriptServiceClient.ts b/extensions/typescript-language-features/src/typescriptServiceClient.ts
index 59f836524b8..7615436bd5d 100644
--- a/extensions/typescript-language-features/src/typescriptServiceClient.ts
+++ b/extensions/typescript-language-features/src/typescriptServiceClient.ts
@@ -972,16 +972,16 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 						spans: diagnosticEvent.body.spans,
 					});
 				}
-				break;
+				return;
 			}
 			case EventName.configFileDiag:
 				this._onConfigDiagnosticsReceived.fire(event as Proto.ConfigFileDiagnosticEvent);
-				break;
+				return;
 
 			case EventName.telemetry: {
 				const body = (event as Proto.TelemetryEvent).body;
 				this.dispatchTelemetryEvent(body);
-				break;
+				return;
 			}
 			case EventName.projectLanguageServiceState: {
 				const body = (event as Proto.ProjectLanguageServiceStateEvent).body!;
@@ -989,7 +989,7 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 					this.serverState.updateLanguageServiceEnabled(body.languageServiceEnabled);
 				}
 				this._onProjectLanguageServiceStateChanged.fire(body);
-				break;
+				return;
 			}
 			case EventName.projectsUpdatedInBackground: {
 				this.loadingIndicator.reset();
@@ -997,56 +997,66 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 				const body = (event as Proto.ProjectsUpdatedInBackgroundEvent).body;
 				const resources = body.openFiles.map(file => this.toResource(file));
 				this.bufferSyncSupport.getErr(resources);
-				break;
+				return;
 			}
 			case EventName.beginInstallTypes:
 				this._onDidBeginInstallTypings.fire((event as Proto.BeginInstallTypesEvent).body);
-				break;
+				return;
 
 			case EventName.endInstallTypes:
 				this._onDidEndInstallTypings.fire((event as Proto.EndInstallTypesEvent).body);
-				break;
+				return;
 
 			case EventName.typesInstallerInitializationFailed:
 				this._onTypesInstallerInitializationFailed.fire((event as Proto.TypesInstallerInitializationFailedEvent).body);
-				break;
+				return;
 
 			case EventName.surveyReady:
 				this._onSurveyReady.fire((event as Proto.SurveyReadyEvent).body);
-				break;
+				return;
 
 			case EventName.projectLoadingStart:
 				this.loadingIndicator.startedLoadingProject((event as Proto.ProjectLoadingStartEvent).body.projectName);
-				break;
+				return;
 
 			case EventName.projectLoadingFinish:
 				this.loadingIndicator.finishedLoadingProject((event as Proto.ProjectLoadingFinishEvent).body.projectName);
-				break;
+				return;
+
+			case EventName.createDirectoryWatcher: {
+				const path = (event.body as Proto.CreateDirectoryWatcherEventBody).path;
+				if (path.startsWith(inMemoryResourcePrefix)) {
+					return;
+				}
 
-			case EventName.createDirectoryWatcher:
 				this.createFileSystemWatcher(
 					(event.body as Proto.CreateDirectoryWatcherEventBody).id,
 					new vscode.RelativePattern(
-						vscode.Uri.file((event.body as Proto.CreateDirectoryWatcherEventBody).path),
+						vscode.Uri.file(path),
 						(event.body as Proto.CreateDirectoryWatcherEventBody).recursive ? '**' : '*'
 					),
 					(event.body as Proto.CreateDirectoryWatcherEventBody).ignoreUpdate
 				);
-				break;
+				return;
+			}
+			case EventName.createFileWatcher: {
+				const path = (event.body as Proto.CreateFileWatcherEventBody).path;
+				if (path.startsWith(inMemoryResourcePrefix)) {
+					return;
+				}
 
-			case EventName.createFileWatcher:
 				this.createFileSystemWatcher(
 					(event.body as Proto.CreateFileWatcherEventBody).id,
 					new vscode.RelativePattern(
-						vscode.Uri.file((event.body as Proto.CreateFileWatcherEventBody).path),
+						vscode.Uri.file(path),
 						'*'
 					)
 				);
-				break;
-
+				return;
+			}
 			case EventName.closeFileWatcher:
 				this.closeFileSystemWatcher(event.body.id);
-				break;
+				return;
 
 			case EventName.requestCompleted: {
 				// @ts-expect-error until ts 5.6
@@ -1063,7 +1073,7 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 						})
 					);
 				}
-				break;
+				return;
 			}
 		}
 	}
@@ -1148,13 +1158,9 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 		this.watches.set(id, disposable);
 	}
 
-	private closeFileSystemWatcher(
-		id: number,
-	) {
+	private closeFileSystemWatcher(id: number) {
 		const existing = this.watches.get(id);
-		if (existing) {
-			existing.dispose();
-		}
+		existing?.dispose();
 	}
 
 	private dispatchTelemetryEvent(telemetryData: Proto.TelemetryEventBody): void {