Could you not be able to edit your app? It would still show Loading... ?
Based on the issue that you mentioned, I have made a test on my side, and don't have the issue that you mentioned.
Please consider clear cache of your browser, then sign in PowerApps again, run your app again, check if the issue is solved. Also please take a try to re-start your machine, then run your app again, check if the issue fixed.
If you could not edit your app within your browser, please consider edit your app using the following previous PowerApps version: