[keycloak-user] Blacklisting/whitelisting of domains for email entered during user registration

Hi, Is there this feature (i was not able to find it) in Keycloak or is it planned (I was not able to find it in JIRA)? It is extremely useful (mainly blacklisting) in some cases. Eg. yesterday we fought spammers in one of our public systems. Spammers registered lots of new users using disposable email service and then used them to create spam content. We blacklisted domains used by the disposable email service from registration, which stopped spammers immediately. We do not use Keycloak there yet, but maybe in future. Current system we use has blacklisting available OOTB. Registration email whitelisting may be useful if you create service for eg. your employees only, and want them to register there with company emails only. I think it should be possible to add new step into "Registration" flow to perform this blacklisting, we can do it yourself probably, but it should be cool to have this very useful feature present in the Keycloak out of the box. WDYT about this feature, can I create jira feature request for it? Vlastimil -- Vlastimil Elias Principal Software Engineer Developer Portal Engineering Team