Seedvault backup provider not available in secondary profiles

Expected Behavior

Sign into 2ndary profile, open Settings -> System -> Backup and select "Seedvault Backup" under "Change backup provider"

Current Behavior

I get an empty list/page when opening Settings -> System -> Backup and selecting "Change backup provider"

Steps to Reproduce

Sign into 2ndary profile, open Settings -> System -> Backup You'll note that the top entry reads "Backup" (No account is currently storing backed up data) instead of "Seedvault Backup" (Backup status and settings). On our Pixel devices we run GrapheneOS, which also ships with Seedvault built-in and secondary profiles can be backuped (and successfully restored), which is of utmost importance for us. I can imagine that this isn't a device model specific problem, but more likely a general Seedvault-in-AOSP implementation problem. Maybe GrapheneOS repo might help solve that one, since they had the same issue about a year ago.

Device information

/codename pro1x /version lineage-21 /date 2024-10-07 /kernel 4.19.318-perf+ /baseband MPSS.HA.1.1-00140-KD_ALL_PACK-1 /mods none

I have read the directions.