Does it happen when you have no Chrome extensions?
Easy way to test that is to download Chrome Canary, a dev version of Chrome, and a good browser to use Webflow when you want to be sure nothing is interfering with it.
What can also be one is to test in an entirely new user session on your mac or windows computer.
I haven’t had it reset @alexdixon and @vincent, but I have had the whole text erased before. So rather than it showing the previous alt text, whatever I had typed before disappeared. Maybe the two bugs are related?