diff --git a/packages/preferences/src/browser/abstract-resource-preference-provider.spec.ts b/packages/preferences/src/browser/abstract-resource-preference-provider.spec.ts
index 845cd97bc0527..f7279133c1bf4 100644
--- a/packages/preferences/src/browser/abstract-resource-preference-provider.spec.ts
+++ b/packages/preferences/src/browser/abstract-resource-preference-provider.spec.ts
@@ -36,6 +36,7 @@ import { MonacoTextModelService } from '@theia/monaco/lib/browser/monaco-text-mo
 import { Disposable, MessageService } from '@theia/core/lib/common';
 import { MonacoWorkspace } from '@theia/monaco/lib/browser/monaco-workspace';
 import { PreferenceSchemaProvider } from '@theia/core/lib/browser';
+import { EditorManager } from '@theia/editor/lib/browser';
 
 disableJSDOM();
 
@@ -84,6 +85,7 @@ describe('AbstractResourcePreferenceProvider', () => {
         testContainer.bind(<any>MonacoTextModelService).toConstantValue(new MockTextModelService);
         testContainer.bind(<any>MessageService).toConstantValue(undefined);
         testContainer.bind(<any>MonacoWorkspace).toConstantValue(undefined);
+        testContainer.bind(<any>EditorManager).toConstantValue(undefined);
         provider = testContainer.resolve(<any>LessAbstractPreferenceProvider);
     });
 
diff --git a/packages/preferences/src/browser/abstract-resource-preference-provider.ts b/packages/preferences/src/browser/abstract-resource-preference-provider.ts
index 37477445a9b1e..523bff9f67ac6 100644
--- a/packages/preferences/src/browser/abstract-resource-preference-provider.ts
+++ b/packages/preferences/src/browser/abstract-resource-preference-provider.ts
@@ -195,6 +195,7 @@ export abstract class AbstractResourcePreferenceProvider extends PreferenceProvi
                         success = true;
                     } finally {
                         this.readPreferences();
+                        await this.fireDidPreferencesChanged();
                         this.pendingTransaction.resolve(success);
                     }
                 }));