Rated 5 out of 5 stars

Great first help for frustrated TB 2 lovers who dislike the new search stuff in 3.1. Thank you very much! Makes TB 3.1 at least usuable after all!

I just wonder if it would be possible to add an option to turn the global search box into the old quick search box, i.e., bring back the feature to select filters with a drop down menu from the search field itself,i.e., dismissing the search bar completely.
Because when it jumps in now it still takes a lot of space and this is not so good on small laptop screen (we disabled the tab bar for that reason).

Do you think this could be done as an additional option? I've no idea how difficult it is to write such an extension, so maybe I'm asking for sth. impossible...

This review is for a previous version of the add-on (0.4.2). 

Thanks Frank, I read your comments at bugzilla also about your experience with my extension, and your replies to another users trying to explain how 'Unified Search' works. I appreciate it (and specially because I express myself badly in English ;-)
Note that in release 0.4.3 I solved one bug commented at bugzilla: the global search box must be hidden if Thunderbird option 'Enable global search and indexing' is disabled plus Unified Search option 'Enable filtering from search box' is disabled too (this two features disabled means that search box is not needed), and two bugs more about persistent filters (more info in the release notes).

Currently, I don't want modify the current global search with more functionality (like the TB2-style drop-down list) for simplicity, and the 'Auto-show filter bar' option was an easy&quickly mode to allow use the extra filtering features (you can disable the 'auto-show' and open it manually only when needed) but I'm thinking in create another standalone 'box' in the toolbar like proposed in mockups of Bug 570815, with both global search and filtering features; and the 'standard' global search box and filter box&bar may be hidden. I think is the best solution.

Thanks for the feedback,
IagoSRL