Yeah this. ^ I am not going to wilfully support someone, no matter how stupid or reckless their behaviour just because we both happen to have a vagina!
I also hate 'HANDHOLD PLEASE!' and will never go onto a thread where someone is asking for this. Why does anyone want someone to hold their hand? How is that going to help anyone?! 
'Am I pregnant?' Followed by a negative pregnancy test. (And how is anyone reading Mumsnet going to know?!)
Use your words. (Who the fuck started this bizarre and irritating phrase?!)
'Have you thought about using mounjaro?' on any thread where someone says they want to lose weight. (Often posted within the first 5-6 posts!)
People using 'boomers' and 'Karen' as an insult.
The competitive teeny-tiny eating.
The posters that regard anything over a size 8 as fat!
Anti-semitism.
'Food noise.'
'Man here.'
People who say 'sky fairy,' and imaginary friend' when someone talks about God or Jesus. These same rude feckers never say anything against ANY other religion, just Christianity.
Also roll my eyes to the back of my head at the instant accusation of racism to ANYone who shows any worry or concern at the number of boats coming across the English Channel.
There's loads more, but I would be here all night! 
!