Hi @Lomrjyo thanks for the report! Could you share a screenshot and let us know which gadgets you have enabled?

@Jdlrobson here is a screen recording

Gadgets:

This looks like Wikieditor not VisualEditor (unless I'm mistaken). @Samwilson any ideas what could be happening here?

Yes, I agree that it looks like WikiEditor.

@Lomrjyo I notice that you've got the DotsSyntaxHighlighter gadget enabled, but the styles shown in your screencast don't match that so I thing you're also using CodeMirror (i.e. the highlighter button in the toolbar). These two things shouldn't be used together, and I wonder if there's some strange interaction going on between them because they both provide a means of resizing the editing area (and thus perhaps throwing off the alignment of the text and selecting, as you're seeing). Could you disable the gadget and see if the problem persists? If it's still happening, could you do another screenshot but include the toolbar this time? Thanks!

@Samwilson I disabled it but could still reproduce the bug (see attached)

Thanks for that.

Looks like it is VE's wikitext editor after all.

It might still be an interaction with a gadget or userscript. Can you try with safemode=1? There is some other info about debugging this sort of thing at https://www.mediawiki.org/wiki/Help:Locating_broken_scripts

It ended up being a userscript problem

@Lomrjyo glad to hear the issue is resolved! Which userscript was the problem? Would be good to know if anyone else hits the same issue!