Welcome to Firefox for Android Add-ons.
Add extra features and styles to make Firefox for Android your own.
CloseReview for Mark All Read Button by Firefox user 6c38bb
Rated 5 out of 5 stars
There is a way to "mark all read":
Choose "mark" on the Thunderbird and then choose "mark all read" from the dropdown menu that appears.
The downside (aside from needing several mouse actions) is that a message must be selected for the "mark" button to be active. The keyboard shortcut "shift-c" does not have this restriction.
To create your own collections, you must have a Mozilla Add-ons account.