This just happened to me and I don't have access to the cloud to save my project. I have to go and download each layer separately to be able to save my progress
Basically I don't think it's necessarily "broken" - but rather, that's how it's supposed to work. I know some drawing apps purposefully use that so it's easier to erase. I agree, it's pretty annoying tbh. But also, if you can't undo the erase, then that part of it is probably broken. Maybe try asking in the "bugs and issues" forum?Hope this helps :)
Antti
Hope Wilson
koi
Antti