Credentials "bound" to the folder do not show in the credentials dropdown

Repro:

• Install the Folders plugin
• Create a Folder
• Configure the Folder to have a Credential Domain, then a dd a Perforce Password credential to that domain
• Create a job within the folder with SCM Perforce. View credentials from the dropdown

Expected: pick from global credentials and the credential just added in the folder's credential domain.

Actual: only global credentials.

I do have project team specific folders on the master and each has a local credential store that is visible only to users with the permission to create jobs in that folder. But the P4 plugin doesn’t see those credentials – it only sees the ones at the master level.