I saw that there is already a JIRA issue for this, but I was wondering whether there are any plans to add support for i18n in keyclaok themes? 

Here's the issue: https://issues.jboss.org/browse/KEYCLOAK-301

To be more precise, we'd need to provide different messages and labels in log-in and registration templates based on the browser language. 

Cheers,

Nils