Funnily enough, Brontornis does now most frequently get placed in Anserimorphae alongside waterfowl, whereas it was previously most often thought to be a terror bird (though I should say there’s still plenty of debate). It’s thought to be heavier than any terror bird at possibly as much as 400kg - where the average horse apparently weighs 500kg.
Being extinct, I assume no one ever told it how to get to Sesame Street.
I’ve not used LibreWolf, but assuming that Firefox addons are generally compatible, it might be worth trying Chrome Mask. It’s made by a Mozilla employee.