The pop up window does show, but there is a warning in the window that the PDF file is damaged.
Fields list in snapshot record does not match fields list in 'course'. Record is missing fields: scProductID, CEU
- line 876 of /lib/classes/event/base.php: call to debugging()
- line 53 of /mod/certificate/view.php: call to core\event\base->add_record_snapshot()
I don't know if the database was damaged when converting to innodb or if the moodledata folders were damaged in the upgrade.
I installed a different certificate module (simple certificate) and it seems to work ok.