Huggle 2.1.23 doesn't do that, and MediaWiki's rollback doesn't do it either. If HG3 is using the edit API
https://www.mediawiki.org/w/index.php?title=API:Edit#Editing_pages
there is the option to set 'watchlist' to 'nochange'.
See also bug 66215.
Version: 3.0.1
Severity: normal