Brave taking cryptocurrency donations “for me” without my consent

I'd been really loving Brave and using it as my daily driver for a few months now, until that I noticed that little "Brave Ads" icon at the end of the address bar. That's when I realized their entire business model is just in the usurpation of existing Google ad revenue, dressed up with "privacy concerns" for the good PR. This sent me on a journey to find a really solid, free, Chromium based browser that is totally de-Googled, which seems absolutely impossible. I've tacitly settled on Vivaldi, but it's just impossible to really know if they are trustworthy as a company in the long run. Ultimately I feel like I can only trust a browser who's entire build process is open source at this point.

Honest question. Why not Firefox? What are your concerns with it?

I've tried over and over for decades to like Firefox, but I just don't. I can't say it's a rational decision entirely. But beyond that, I just think that Mozilla's motives can't really be trusted at face value with the amount of revenue they have these days, and their whole profile sync service. It just comes down to incentives, and any company which collects any kind of data has the incentive to profit at our expense regardless of ideology. Especially where people's salaries could depend on it.