Love the browser; one possible issue I have discovered so far:
At the login screen for YNAB [https://app.youneedabudget.com/users/login], the blue background flickers.
I have turned off hardware acceleration in Prefs > Advanced but the issue persists.
Same with shields up or down.
Was running Flux but same issue after quitting that app.
Issue is not present in a different browser (Firefox).
Using Brave 0.12.15 on macOS Sierra 10.12.2.