Rated 4 out of 5 stars
Great extension, but I have a few suggestions
1. Tab completion works only with the starting sub-string of a path, it doesn't work with sub-folders even if there is only one matching sub-folder. What's worse, after pressing tab the suggestions disappear and you have to escape and activate the selection mode again.
2. I suggest renaming 'save' to 'move' (more intuitive)
3. It would be nice to be able to set the option "restrict to the current server" only for "copy" and "save/move" command, not for "go", as perhaps most people rarely move messages across different accounts.
4. Shortcut tips in the status bar should comply with custom shortcuts; option to remove these tips.