MDL-59854 has been fixed, but there is a typo in the code used to do this which triggers under the following circumstances:

• auto-subscription enabled
• course backed up with users and user data

Unfortunately the DB table mdl_hsuforum_subscriptions appears in one code block of backup/moodle2/restore_hsuforum_stepslib.php as mdl_hsuforum_subscription (no 's'). This means that the restore process fails under the above conditions with the error 'Table "hsuforum_subscription" does not exist' - which indeed it does not.