Rated 4 out of 5 stars
"Expression Search" works well, but I wish it integrated with Thunderbird Conversations to really emulate GMail.
But what about "GMailUI"? I used to use this extension to switch to GMail's keyboard shortcuts, yet this functionality seems to have been removed since then? Please restore this functionality, I keep inadvertently marking all my messages as junk!
Compared with original GMailUI 0.6, these features are still missing:
Use 'Y' to archive selected mail to archive folder (use 'a')
Use J/K to move messages up and down, and Ctrl+J to mark a message as junk (conflict with builtin key mapping, use 'f/b' instead)
Key '/' focuses on the quick search bar (use Ctrl+F)
Please try http://kb.mozillazine.org/Keyconfig_extension for change key config.
Sorry for the inconvenience.