Rated 3 out of 5 stars
After updated to ver. 3.12 (Xubuntu 13/04-64, Thunderbird 24.0) all accounts do not check on startup!
When this add-on switch off - all OK.
can you file a bug...
You can raise a bug report here:
or contact me directly from there to help you fix the problem. Also try 3.12.1 which was just released to see if that helps you.