Rated 4 out of 5 stars

Love this --- rediscovering Thunderbird and needed an alternative to MsgFiler for Apple and SimplyFile for Outlook/PC.

Only problem is I couldn't create a short cut that used a DIGIT rather than a letter. I wanted to use ALT-9 (just because that's how I had the other two filers configured) but Quicker Filer only seems to allow letter combinations.

Also, the dialog width needs to be much longer so you can see the actual selection when you have nested folders.

This review is for a previous version of the add-on (0.5.1). 

I'll add digits for the next version. The dialog you can easily resize and the new size will be stored and used the next time the dialog is recalled.