Edge does not prompt for credentials on file links

Hello,

We use the IntranetFileLinksEnabled policy to access file:// links inside our intranet.
It works pretty good so far, except for one issue.

The first time we access a new UNC path, say file:////server-a/, Edge will correctly ask which application to launch "file" with, but afterwards nothing happens. The Windows prompt for credentials does not show up.

We have to access \\server-a\ in the file explorer and register the credentials (or add it in the credential manager) for those file:// links to work since Edge is not able to prompt for credentials.

Is this a known bug or is it intended? Do we have an available policy or configuration to authorize a prompt for credentials from Edge ?

Thank you in advance for your insights.
Regards.