Has your friend got a SSD or a normal hard drive?? Ram can be a thing too, how much ram has she got? Sorry for the Spanish inquisition 
I suspect her computer doesn't have a lot of ram -- probably 4, maybe 6 GBs of ram. And, yes, it's a normal hard drive, not an SSD. That one particular computer has ALWAYS had a choppy experience with FF.
I wonder if keeping Brave, but adding uBlock Origin to it, would override the defects of Brave's added code that have now been been brought to light. I would assume, yes, but I don't know for certain.

P.S.
And thanks for the Monty Python clip.

I'm not a fan of Brave simply because they are attempting to control web advertising (actually in a quite bullying way, but that's another story) .. this IMHO puts them in a position which will inevitably be in conflict with the interests of their userbase.
But they'll fail anyway....
After reading that article, I'm much less of a fan of Brave today than I was yesterday. But, in this particular case, do you think uBlock Origin might override that code with the Facebook permissions?
I would think it should, but I don't know.

(I do know that uBlock Origin is a mighty little beast.)
And, yes, there is a conflict of interest with Brave, and I can clearly see it now.
Facebook? Please...
