Update src/extension-support/extension-worker.js

src/extension-support/extension-worker.js

@@ -87,6 +87,9 @@ Object.assign(global.Scratch, ScratchCommon, {
     canGeolocate: () => Promise.resolve(false),
     canEmbed: () => Promise.resolve(false),
     canUnsandbox: () => Promise.resolve(false),
+    canScreenshotCamera: () => Promise.resolve(false),
+    canDownload: () => Promise.resolve(false),
+    download: () => Promise.reject(new Error('Scratch.download not supported in sandboxed extensions')),
     translate
 });
 
@@ -98,4 +101,4 @@ global.Scratch.extensions = {
     register: extensionWorker.register.bind(extensionWorker)
 };
 
-global.ScratchExtensions = createScratchX(global.Scratch);
+global.ScratchExtensions = createScratchX(global.Scratch);