Welcome to Firefox for Android Add-ons.
Add extra features and styles to make Firefox for Android your own.
CloseReview for Extra Folder Columns by Fabio Esquivel
Rated 5 out of 5 stars
Will it ever be adjusted for Thunderbird v38.0.1?
Nevermind, I just checked for the fix:
Set check mark on "View/Layout/Folder Pane Columns" and normal operation will return.
To create your own collections, you must have a Mozilla Add-ons account.