[@robin-w Moderator 6 years, 11 months ago]

visbility hidden should make a forum only visible to moderators and keymasters

If you are not seeing that then it could be a theme or plugin issue

Themes

As a test switch to a default theme such as twentyfifteen, and see if this fixes.

Plugins

If that doesn’t work, also deactivate all plugins apart from bbpress and see if this fixes. if it does, re-enable one at a time to see which is causing the error.

Then come back