I installed from http://download.moodle.org/plugins/mod/certificate.zip, and I am not sure if this is the same as HEAD
installtion was ok, but I got
Capability "mod/certificate:view" was not found! This should be fixed in code.
- line 579 of /lib/accesslib.php: call to debugging()
- line 1026 of /lib/accesslib.php: call to has_capability()
- line 22 of /mod/certificate/view.php: call to require_capability()
same with review.php