Are you tired of clicking Thunderbird's "Smart Reply" button and accidentally only replying to the list? Do you participate in open source mailing lists whose policy is to always reply to everyone rather than just the list? Do you get irrationally angry that there is no way to disable "Reply List" functionality?
This add-on is for you! It adds a new "Reply All" button which can replace the "Smart Reply" button in the message action toolbar. It will always reply all, and never reply list.
Optionally, you can have it always reply with plain text instead of defaulting to HTML format.
You will need to configure the message display tab to remove the Smart Reply and move the Reply All button to your preferred location in the action list.
Reply All Button on addons.thunderbird.net.
Pack the add-on as an .xpi file and install it from the “gear” menu in Thunderbird's add-on manager.
On UNIX-like systems, you can create the .xpi file by simply running:
$ cd seams/
$ make