The Brief: OOMF is an acronym for "one of my followers" or "one of my friends."

Bluesquiggle
DEEP DIVE

On Twitter, OOMF stands for “one of my followers.” It can be a way to call someone out without directly naming them.

https://twitter.com/notviking/status/1285315603448782849

https://twitter.com/vantefIwr/status/1285606857328013321