I noticed that too, i think chrome updated their blocking. I figured out i was able to allow the pop up after it gave the error message. Did you try to click the pop up message and choose "allow"? its a button that comes up on the right side of the URL at the top of the browser. i'm going to work on that further though. let me know if it doesn't work though
I'm using Brave, which is chromium based with its own adblocker built in. Don't think it has allow buttons for one time things, but maybe i'm missing something.
-Edit- I'm on Linux, but was able to get on with Firefox. Brave didn't show a prompt for allowing to open a new window. (lost my save data though switching browsers, but makes sense if you are storing them in a local cache)
Cloud saves should be 100% functional BUT i didn't build with ad blockers in mind. that is interfering with the cloud saves so most likely the data was only saved locally and not saving properly to cloud. That is crucial that you brought that up so thank you. I will try a workaround to work with adblockers. Thanks for bringing that up.