It looks like the editor has inserted a bunch of junk.

Copy the code from the working survey with the editor in source mode and paste it into the new survey with that editor also in source mode.

Hi,
thanks. Unfortunately that's exactly what I did. From source mode to source mode editor. Do I have to activate any particular thing for this type of question?

update:

Btw I've managed to export/import the question in my survey with no issues and it works at first, but..as soon as I change the question code or edit any part of the question (tried with both editors), the HTML breaks..!

Ok it seems there's somethign going on with the HTML editor and copy/paste.
Current solution: write the html in Atom (or any other text editor) and then copy the whole thing in the question field. Not very practical but at least it works for now.
I'd be happy to know more about the issue as basically I cannot edit anything from limesurvey question editor (or it will break again)

Yes, I know about this problem with HTML brackets.

My workaround is to enter it, save it, and never touch again.

Joffm

I see, thanks! Is there an issue open about it?

I would switch the editor off anyway. Those editors generally only cause more problems than they help.

Editor on demand only.

Allowed in 3, not in 4 ....

Editor on demand only. Allowed in 3, not in 4 ....

Yeah, this is what I use in LS3. Just checked, an really, this is not an option in LS4 anymore. A step back...