We're on Moodle 3.3.2 and an issue has arisen in one of our oldest courses. The topic 0 in this course is showing as 'hidden from students' and there does not appear to be any way of changing this. I just don't have the menu options at my disposal to unhide topic 0. I'm wondering if in the dim and distant past topic zero was set to hidden in some way and there's no way I can now unlock this? This is just happening in this particular course which makes me think there's some legacy setting in play here.
The course has been using the Onetopic course format for many years. Other courses that have also been using Onetopic are not affected in the same way. When I revert this course to Topics format I still cannot make topic 0 visible.
This screenshot shows the issue:
The following screenshot shows that there is no option to edit the visibility of topic 0 when the course is in Topics Format and editing turned on.
Any activity or resource I place in Topic 0 is also hidden from students suggesting that the section has a hidden setting running.