Hi
If you open the custom HTML module with the “code” tab for the first time, everything goes without a hitch, it's only when you open the module for the second time that it happens and then it's the same every time you open the module in "code" mode, maybe it's related to a session issue?
Nope, I can open the "Image" custom HTML module in code mode, using JCE (latest) 10 times in a row and 4AI opens up as expected. That's not it. I don't think this is coming from 4AI to be honest.
We can see in your screenshot that it's JCE throwing an error ("iframe.getSelection is not a function") and whatever the circumstances, it's still where the error happens, not inside of 4AI, so I don't even have anywhere to look at in 4AI. Because the error happens in JCE.
Best regards
Yannick Gaultier
weeblr.com / @weeblr