Is using Keycloak embedded with spring boot a bad idea or not?

I working on a legacy project that uses Keycloak 11. recently, I found this repository I realized that we can use Keycloak embedded with Spring Boot. So, I moved the project this way but there was a problem. When I tried to make it clustered I faced a problem described here on

When I sent this question to someone that working on keycloak, they said that this isn’t a good idea because the upstream project (Keycloak) doesn’t support this way.

So, I want to know what to do and what not to do. how can I solve my problem and what will happen when I upgrade the version of keycloak from 11 to newer (e.g. 21) in this way?

As Keycloak said on their website, they are using Quarkus on the newer version. can I use the new version of Keycloak embedded with Spring Boot?