Setting User info signed response algorithm to unsigned (v.19.0.3 ->)

Hello, I hope someone could clarify the User info signed response algorithm setting that is found as follows in Keycloak v.19.0.3:

Clients → (choose client) → advanced → Fine grain OpenID Connect configuration → User info signed response algorithm

The problem:
In older versions of Keycloak (e.g. v.16.1.1) when selecting “unsigned” it was actually selected in the dropdown menu. When trying this in newer versions (v.19.0.3 and v.20.0.3) selecting “unsigned” gives a blank field.

As I am a new user I can only post one image, so I compressed the screenshots to one example

Could someone please confirm whether unsigned is actually being set in versions 19 and 20 or if it is a bug? Many thanks in advance. If you need any further information, please let me know.