There is no Add-On to READ .maff files on a Macintosh
The add-on titled "Mozilla Archive Format" will CREATE .maff archives, but will not OPEN them. In this thread https://support.mozilla.org/en-US/questions/1059827 I was advised to find a separate Plug In to read them. I searched the Addons for "maf" and ".maf" and ".maff" and "maff" and THERE ARE NO PLUG INS TO READ THE DAMN FILES !!! Searching the net in general yields spam - articles about what the format is, and references mostly to items that run on a PC.
Wšykne wótegrona (4)
Try this extension. https://addons.mozilla.org/En-us/firefox/addon/mozilla-archive-format/
Also, I have used Get Info on several .maff files to tell it to open itself with Firefox, but I cannot select FireFox. It's greyed out in the window. WTF ???
See also this previous thread:
3.1.0.1 is installed. A slightly earlier revision is the file extension allowed me to create them in the first place. But I cannot select Firefox as the file opener. Its greyed out in the menu list.