Rated 4 out of 5 stars

Its working on my desktop but I just tried to add it to my laptop and it won't install because it says not supported!One thing that might be the answer is I made a back up of my Thunderbird using MozBackup and it might have been an older version of Thunderbird ,(not sure)And I restored over an up-to-date Thunderbird.Maybe that's why it accepted it.Its a great add on, would be a shame if this isn't updated.I don't understand why its not an option in Thunderbird by now.

EDIT
http://extensions.sanjer.nl/index.php?page=tb_cs_prerelease#changelog
this one works.
This is odd.
I have this version on my desktop and I use Add On Collector to sync both machines. But its not syncing the right version over to my Laptop, A manual download from the above link fixed it.