OAuth completely broken in Firefox

[mcguirev10]

As the subject says, OAuth is totally broken in Firefox on Windows. This happens for the Community login, the Dev Dashboard, and PKCE flows that pop up a user login window.

I'm not sure whether it's relevant, but the F12 browser dev console is full of Content Security Policy errors.

Also, is it just me or is the discussion forum using completely bizarre, nearly-unreadable font and color combinations? Mint green on white? I feel like I'm going blind here (and since I never use MS Edge, it's a bare-bones installation, no weird plugins or anything).

For what I pay for this service, I'm not at all impressed...

[zcorpan]

If this works in other browsers you can report an issue on webcompat.com