Mastodawn

Twitter abandoned their trademark, all the ActivityPub sites are twitters (lowercase t) now

(normally you get lawyer letters for using a TM like Kleenex® or Band-Aid® as a generic word but I doubt that the company formerly known as Twitter is paying that legal bill)

https://www.legalzoom.com/articles/the-problem-of-genericide-in-trademarks

The problem of genericide in trademarks

Sometimes a company's branding can become so pervasive in our culture it goes beyond the traditional confines of its trademark. What seems like a good problem to have can actually create a new public relations headache known as genericide.