:31:42520 ​ My browser / operating system: Windows 7, Firefox 72.0, Flash 32. If you don't understand what exactly you are doing here, you should close this window without doing anything. If someone told you to copy-and-paste something here, don't do it! It could allow them to take over your Scratch account, delete all of your projects, or do many other harmful things. Stop! :31:42520 This is part of your browser intended for developers. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing). :31:42520 Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at. However, that might be more annoying than leaving the window open. There is a way to ask the user for extra permissions.

However, if it is launched from a regular URL, then as you know it doesn't work. :6:8768 storage warn Deprecation: Storage.addWebSource has been replaced by addWebStore. If you launch the initial Firefox window using window.open, then window.close should work on it. :6:8768 onmozfullscreenerror is deprecated. Console log: onmozfullscreenchange is deprecated. Same way on Scratch 3 on desktop, but I thought that's because of using Windows 7 while Win10 required (why? Isn't Scratch made on Electron?). I created a new project, clicked “Go” and nothing happens.