It looks like the dark mode has been removed from the flags experimental features.
Where it overrides everything to be black.
Also as per this original post about a white page when loading a new tab.
Compared to safari when I open 15 new tabs from a bookmarks folder, the tabs load in the background. In brave they have to load each time I open a tab.
I might have to go back to safari 
I wish brave search was available as a default in safari. I’ve been using xSearch safari extension to change the search default. But I’m placing a lot of trust in that developer that when they say there’s not data collection. Trust that it is the truth today with their code and they won’t change it in the future.