v2.0.0 does not play well with Mail Summaries v1.1 Rated 5 out of 5 stars
When using CompactHeader 2.0.0 and Mail Summaries 1.1 are installed in Thunderbird 9, the title for the main tab does not update properly. The main tab title contains a folder icon with no text most of the time, but it will properly display the account name if an account is selected in the sidebar. However, clicking on a particular folder in the sidebar (inbox, outbox, etc.) does not update the tab title to show the folder name and account.
Great extension though. I have always loathed Thunderbird's huge header display.
I cannot reproduce your problems with CompactHeader and Mail Summaries. Could you please give some more hints (at the support thread at http://forums.mozillazine.org/viewtopic.php?f=29&t=1405155