AIUI VisualEditor has a "wikitext markup detected" warning when the user types wikitext in the wrong place, but it seems to miss some common use cases (well, common at least in hu.wp where the Help: pages are still blissfully unaware of VE and people sometimes get confused and don't realize the tips refer to a different editor):
- https://hu.wikipedia.org/w/index.php?title=Lantos_Piroska&diff=16305068&oldid=16302618 - the user probably copypasted wikilink markup into the main VE edit area. Typing [[ opens the link menu but copypasting it does not.
- https://hu.wikipedia.org/w/index.php?title=K%C3%B3taj&type=revision&diff=16289868&oldid=15829492 - user typed <ref> markup into the cite dialog. (Note also that the standard parser errors out on this but parsoid does not.)