Please see https://invisioncommunity.com/forums/topic/434935-limited-email-content/?do=findComment&comment=2717205
That was a bug/oversight, but fixed
Contact, Warning, Tickets, are not stripped/truncated.
We have also the backend code to exclude any other email which you need (we'll do this for free) just contact us
We want to make this configurable by the admin, but hadn't time for a complete rewrite, which is needed to enhance this further.