Claws wants to synchronise folders after going offline
 

I set up Claws to work with my INBOX (GMail IMAP) as an offline folder and automatically sync the mails whenever the server is polled, so far so good.

But what bugs me is that when I turn the tablet into offline mode Claws somehow gets triggered and asks me in a message box if I want to synchronise my folders.

I don't, and anyway: Now it would be too late, the tablet is already offline!

Does anybody know how to disable this message box?