Neither. Burn halves the damage of physical attacks. It doesn't halve attack or BP. So being burned has no impact on whether or not a move gets the BP bump to 60.I posted this in the OU metagame thread a day ago and got told to repost here:
hi everyone. Unfotunately you cant see it in screenshot but i found this interaction interesting and i wanted to see if it was known or not? Showdown Halves the damage of a move when you are burnt. in turn 9 of this battle, I tera ground with excadrill and get burnt by flare blitz. Usually earthquake would be 50bp but its raised to 60 with tera. does cartridge work this way? i know showdown halves the power of a move when you are burnt, is that how it usually works or does cartridge halve your attack stat? thanks
This isn't a thread about Showdown's client, but halving BP was arbitrarily chosen as a way to represent physical attacks being approximately half as powerful. If Earthquake was showing 60 BP in the situation you described, that's a bug and should be posted in bug reports.