Mine was a while back. But the facts are (briefly) as follows:
I work in a male dominated profession. Somebody in NY had a great idea to link up all the women in the industry by having a women only secret FB group. The ambition was to forge connections and give each other opportunities. It was hugely exciting and within 24 hours we had 30000 members and there were so many truly incredible exchanges going on. Ground breaking.
Some handmaidens invited a few trans in. You can probably guess the rest.
It started with the language policing to begin with. We'd been starting our posts with 'hello ladies!' 'Hey girls!' Etc. Basically revelling in our secret womens' club. The trans interlopers drew up a furious charter stating that we couldn't use words like ladies, women, girls etc. This drawing up and editing and debating the charter took for fucking ever and then they amended it to include references to periods, abortions etc. Couldn't talk about those etc. Btw. A LOT of women on this forum were writers on womens magazines and they covered womens topics like that, unsurprisingly.
AND ANYWAY. IT WAS A WOMENS' FUCKING FORUM!
Anyway, to bring this sorry tale to a close, the whole focus became about our trans members, all out war ensued and within a week the club had imploded. Oh, and I had a handmaiden call me a bigot 