I know that video. The first problem is that all these videos lack context. Indeed, that's a general wickedness of social media
Yet the one you speak of, the two girls were talking/arguing - when the "heffer" threw the first punch, trying to catch the other girl by surprise. If anyone was "celebrating" it may have been because the initiator herself got a beating. Rough Justice.
In this video, all we see is one (white) woman screaming, trying to get away from her attackers. Although someone claims she said the "N" word, even that isn't a justification for a physical attack. Again, there's no context - but all we see is a woman being beaten who doesn't want any part of it.
At least in that regard, there is a significant difference.
I’m not sure this whole thing wasn’t staged any way. Why did the woman stay there, wouldn’t the normal reaction be to just leave? If would be one thing if she intended to fight and stand her ground, but she clearly have no intention of fighting, then why wouldn’t she just get the hell out of there.
And there is conveniently a person there to shoot the whole thing.
In the longer version of that video it shows some kind of altercation between them while going down a supermarket isle. I’ve heard them calling each other “f...ing b*tch” but no “n-word” not that using the n-word qualifies as a justifiable reason to assault someone like that where serious damage could result. Seems like these types are always pulling up the n-word excuse now even when that slur wasn’t used.