also https://en.wikipedia.org/wiki/Formatted_File_System

and https://en.wikipedia.org/wiki/Flash_file_system

and kind of https://en.wikipedia.org/wiki/Amiga_Fast_File_System

Four file systems named ffs; ffs is popular for file systems

There's another expansion to that acronym that I can think of. I think the joke is implied.

Op’s ffs do not target FreeBSD and it l seems like referenced system is FreeBSD only. Claiming naming rights is a stretch here

That's ahistorical. FFS is the berkeley Fast File System, from BSD 4.2, in 1983.

FFS predates FreeBSD and is in some capacity supported by all 3 major BSDs. I'm fairly confident that Linux actually supports it through the ufs driver ( https://github.com/torvalds/linux/tree/master/fs/ufs ); whether the use of different names in different places makes it better or worse is an exercise for the reader.

Yeah please rename it to JFS (JSON File System). Oh wait...

There is a reason I suggested "filefs"; 3 chars isn't really enough to easily be unambiguous.