Mapping username to “sub” token in 10.0.2

I was mapping the user property “username” to the “sub” token in 9.0.0 and it worked perfectly fine. It replaced the long numerical id in the “sub” field with the username. When switching to latest (10.0.2), I cannot get that to work.

I tried creating a new mapper, passing in the username (user property) to a new token, and that worked. I also tried editing an existing mapper, and that worked as well.

Has anyone tried this with 10.0.2? Seems like a potential bug/regression, unless I’m doing something wrong. Would appreciate any help. Thanks!