Well just over 2 weeks since the last time checkgmail broke and now it has happened again. Slightly different this time in that it still notifies new mails, but you can't do anything with them any more. All the features which make checkgmail the best mail notifier (when it works) are gone. Mark Read, Archive, Report Spam, Delete and the preview mode just hang indefinitely. I have redone all the things I mentioned in my own tutorial (and also the later fixes) and nothing makes any difference.
It makes you wonder if checkgmail is worth it any more
Edit. Some further investigation of this indicates that it is trying to view the message preview (by clicking the message title) that is freezing checkgmail. If I restart the app all other functions are available again, but if I try and view the preview again it just freezes and all the other functions fail. There are no error messages in the terminal, when I click on the title to view the preview it just says 'There is one new message', nothing more.