TYPO3 Core

I just noticed a super annoying and stupid bug while performing a major upgrade from v10 to v11:
I could not login successfully anymore to the backend due to a crazy reason.
I configured my TYPO3 installation to always send me a notification mail whenever someone tries to log into the backend (i.e. setting a valid email address in the field [BE][warning_email_addr] and setting [BE][warning_mode] to 1).
Simultaneously, I configured a login logo for the backend to refer to an image which resides somewhere under fileadmin (backend extension -> login.loginLogo).

With this configuration, the backend login will now always fail due to the exception #1630089406 which is thrown when the notification mail is being rendered. The exception message states 'Resource paths must start with "EXT:"'.
Very funny :-/ - when configuring the backend extension to use the logo it states:
'If set, this logo will be used instead of the TYPO3 logo above the login credential fields (e.g. fileadmin/images/login-logo.png or EXT:my_theme/Resources/Public/Images/login-logo.png or //domain.tld/login-logo.png).'

Obvisouly, one cannot use a logo which resides under fileadmin anymore for the backend login page.