Welcome to Firefox for Android Add-ons.
Add extra features and styles to make Firefox for Android your own.
CloseReview for Next Unread Thread (Mark All Read) by roneo.org
Rated 5 out of 5 stars
To mark a whole folder as read and jump to the next unread message, see this other Add-on by the same author:
https://addons.thunderbird.net/fr/thunderbird/addon/next-unread-thread
To create your own collections, you must have a Mozilla Add-ons account.