receiving posts from ignored and blocked contacts, which then become collapsed.
I discovered this yesterday & today, to my chagrin. Tbh i was unhappy, coz when i've decided that someone is so unpleasant that i never wish to interact [even passively] with them again, i was shocked & unhappy that they still show in my network timeline, albeit collapsed with warning as you said. If i had my druthers, i'd never see any aspect of them again.