This is the case.Hmm, seems odd, but browsing the full version on mobile is better IMO Works as it should.
Yeah, it might be because of a hook, but like you mentioned, it does not make any changes to the mobile theme.This is the case.
Unsure why it broke. IPB staff mentioned disabling all hooks fixes it, but some of those hooks we need. The most recent one was a paid addon, for global sidebars, which is needed for ads but the addon should never have broken the mobile theme functionality. It doesn't touch it.
I've contacted the author of the addon to see if he'll take a look at it. Wasn't a free addon too, so I hope the $20 I spent will entitle to at least a quick look to see what would have caused this.