diff --git a/public/app/core/services/theme.ts b/public/app/core/services/theme.ts
index 30d63375f6b..9dcbdb552e8 100644
--- a/public/app/core/services/theme.ts
+++ b/public/app/core/services/theme.ts
@@ -46,10 +46,7 @@ export async function changeTheme(themeId: string, runtimeOnly?: boolean) {
 
   // Persist new theme
   const service = new PreferencesService('user');
-  const currentPref = await service.load();
-
-  await service.update({
-    ...currentPref,
+  await service.patch({
     theme: themeId,
   });
 }