mod_ouwiki: Error message when switching to Student role just after creating OUWiki activity

[kiratskitizing]

Environment
Moodle - 3.9.2+ (Build: 20201028)
OUWiki - 2020050500

Steps to replicate:

1. Create a course.
2. Turn editing on.
3. Add an OUWiki activity and save it to display the activity.
4. The page will dislay the "View" and "Edit" tab. Do not do anything for that.
5. Click your Username/profile on top right hand corner of the screen.
6. Switch role to "Student"

Result: You will see the message:

Please try to make code omit page parameter when it is null
*line 36 of /mod/ouwiki/basicpage.php: call to debugging()
*line 29 of /mod/ouwiki/view.php: call to require()

Using the Boost theme, it will display quickly and will be covered up by the banner/header. But the message is still there underneath it.