BUG: Cannot authorize with Apple because of bloated request headers (cookies)

[napieralla]

Describe the bug
Apple authorization-popup throws 431 error because the request headers exceed 8 KB in size in total.

To Reproduce
Steps to reproduce the behavior:

1. Use Musish for a long time without clearing browser cookies (approximately a year in my case).
2. Be logged out on musi.sh (logged out from Apple Music).
3. Click either of the two login buttons (splash-screen or top-right corner).
4. Watch popup for authorize.music.apple.com open, instantly redirect to activate.apple.com, and return <h1>Bad Message 431</h1><pre>reason: Request Header Fields Too Large</pre> with status code 431.

Expected behavior
Login-page requesting email and password should show in the authorization-popup.

Screenshots

Browser
Chromium 84

Additional context
The issue appears to affect the music.apple.com domain in general because opening that domain directly returns nothing but a 400 error, as just as many HTTP request-headers are sent to it. Opening either musi.sh or music.apple.com in either a different browser (less cookies) or in a incognito window (no old cookies) works fine.
A total of 8302 characters are being in the authorization header, of which 6920 are cookies.

[napieralla]

Fix

1. Click the little lock in in the top-left corner and then click Cookies.
2. Click Remove.
3. Refresh the popup window by pressing F5 or simply by closing it and opening it back up.

These steps should be similar for other browsers than Chromium.

[napieralla]

I assume there is nothing that we can do about this since the request headers sent with *.music.apple.com are outside of our control. We also won't know if this error is happening to someone as no info about it is returned to us. So I guess the best we can do is keep this issue around to help spread awareness and help people fix this problem themselves.