How to add extra header to Authorize button in swagger

we use a header with api-key (x-api-key) where the user needs to add their api key.
When cliking Authorize i can only add the header for Authorization but would like to have another header there as well, how can i do that?

Also we are using keycloak OAuth2, is it possible to connect this to swagger somehow?

See docs on enabling UseBearerSecurity: