diff --git a/src/browser/setupWorker/glossary.ts b/src/browser/setupWorker/glossary.ts
index ff1540622..23017c6ec 100644
--- a/src/browser/setupWorker/glossary.ts
+++ b/src/browser/setupWorker/glossary.ts
@@ -146,8 +146,8 @@ export interface SetupWorkerInternalContext {
       ServiceWorkerMessage<EventType, ServiceWorkerIncomingEventsMap[EventType]>
     >
   }
-  useFallbackMode: boolean
   supports: {
+    serviceWorkerApi: boolean
     readableStreamTransfer: boolean
   }
   fallbackInterceptor?: Interceptor<HttpRequestEventMap>
diff --git a/src/browser/setupWorker/setupWorker.ts b/src/browser/setupWorker/setupWorker.ts
index 39bb42448..b89376641 100644
--- a/src/browser/setupWorker/setupWorker.ts
+++ b/src/browser/setupWorker/setupWorker.ts
@@ -143,9 +143,9 @@ export class SetupWorkerApi
           })
         },
       },
-      useFallbackMode:
-        !('serviceWorker' in navigator) || location.protocol === 'file:',
       supports: {
+        serviceWorkerApi:
+          !('serviceWorker' in navigator) || location.protocol === 'file:',
         readableStreamTransfer: supportsReadableStreamTransfer(),
       },
     }
@@ -160,11 +160,11 @@ export class SetupWorkerApi
       },
     })
 
-    this.startHandler = context.useFallbackMode
+    this.startHandler = context.supports.serviceWorkerApi
       ? createFallbackStart(context)
       : createStartHandler(context)
 
-    this.stopHandler = context.useFallbackMode
+    this.stopHandler = context.supports.serviceWorkerApi
       ? createFallbackStop(context)
       : createStop(context)