[C2] Fix broken course backup/restore/copy/import #6870
Description
Implement the update of maintenance tool (from 1.11 to 2.0).
/main/course_info/maintenance.php?cid=1&gid=0
The priority is on importing course backups from 1.11.x
{{ message }}
Implement the update of maintenance tool (from 1.11 to 2.0).
/main/course_info/maintenance.php?cid=1&gid=0
The priority is on importing course backups from 1.11.x