It's not my suggestion or preferred browser of choice, but there is also easy alternative option for lazy people, because brave browser supports onion links and it works with Chipmixer.
I would always suggest using Tor browser because it's much more secure, but it's always good to have some easy alternative.
Interesting, I didn't know that Brave browser has that capability (not that I would use it.) I know there are plugins and extensions that allow Chromium to connect to onion addresses, but I don't like involving more links in the chain. Honestly, I'm not a fan of FireFox (putting it mildly) and to this day can't understand why the Tor Project uses it as the basis for their browser.
Can you elaborate on what actually happened and why the website was down for those 3 days?
What is it about privacy that confuses you?