I just downloaded the newest version of Brave and am unable to log in to protonmail.com using it. Protonmail sends me to a screen that says it is only compatible with browsers supported by PRNG and Web Storage:
Turning all the shields off does not help at all.
The site does work as expected when using Chrome.
Brave Version 0.68.132 Chromium: 76.0.3809.132 (Official Build) (64-bit)