[Bug][Firefox only] Account Selector with no Background Color

[onmax]

Steps for reproductions

1. Use a Firefox-based browser (in my case zen)
2. Open wallet.nimiq.com with an account and go to desktop mode
3. Open network
4. Go back

The background of the account selector will disappear.

Without Bg ❌	With background ✅

20250130-1228-23.2595978.mp4