Custom loginhandler no longer works

Hi, we created a custom login handler to dynamically add roles to the user on login. This was working properly in Modeler 6.10.3, however when upgrading our project to 6.10.4 or later, this feature no longer works. We do not see any errors, or things broken, but the system will not add the roles to the user.

Do you have any suggestions or more info if this feature is still supported?