diff --git a/src/vs/workbench/api/browser/mainThreadDiagnostics.ts b/src/vs/workbench/api/browser/mainThreadDiagnostics.ts
index eb26b62da3a..ca934673534 100644
--- a/src/vs/workbench/api/browser/mainThreadDiagnostics.ts
+++ b/src/vs/workbench/api/browser/mainThreadDiagnostics.ts
@@ -33,7 +33,7 @@ export class MainThreadDiagnostics implements MainThreadDiagnosticsShape {
 		this._activeOwners.clear();
 	}
 
-	private _forwardMarkers(resources: URI[]): void {
+	private _forwardMarkers(resources: readonly URI[]): void {
 		const data: [UriComponents, IMarkerData[]][] = [];
 		for (const resource of resources) {
 			data.push([
diff --git a/src/vs/workbench/services/keybinding/browser/keymapService.ts b/src/vs/workbench/services/keybinding/browser/keymapService.ts
index 4a22d72e0d3..ea5cd3a04d3 100644
--- a/src/vs/workbench/services/keybinding/browser/keymapService.ts
+++ b/src/vs/workbench/services/keybinding/browser/keymapService.ts
@@ -349,7 +349,7 @@ export class BrowserKeyboardMapperFactoryBase {
 			// The value is empty when the key is not a printable character, we skip validation.
 			if (keyboardEvent.ctrlKey || keyboardEvent.metaKey) {
 				setTimeout(() => {
-					this._getBrowserKeyMapping().then((keymap: IKeyboardMapping) => {
+					this._getBrowserKeyMapping().then((keymap: IRawMixedKeyboardMapping | null) => {
 						if (this.isKeyMappingActive(keymap)) {
 							return;
 						}
diff --git a/src/vs/workbench/services/preferences/browser/preferencesService.ts b/src/vs/workbench/services/preferences/browser/preferencesService.ts
index db55635c1f9..1e52b5bb0b2 100644
--- a/src/vs/workbench/services/preferences/browser/preferencesService.ts
+++ b/src/vs/workbench/services/preferences/browser/preferencesService.ts
@@ -314,9 +314,9 @@ export class PreferencesService extends Disposable implements IPreferencesServic
 	configureSettingsForLanguage(language: string): void {
 		this.openGlobalSettings(true)
 			.then(editor => this.createPreferencesEditorModel(this.userSettingsResource)
-				.then((settingsModel: IPreferencesEditorModel<ISetting>) => {
+				.then((settingsModel: IPreferencesEditorModel<ISetting> | null) => {
 					const codeEditor = editor ? getCodeEditor(editor.getControl()) : null;
-					if (codeEditor) {
+					if (codeEditor && settingsModel) {
 						this.addLanguageOverrideEntry(language, settingsModel, codeEditor)
 							.then(position => {
 								if (codeEditor && position) {