For what it's worth, the sidebar on the wiki seems to change depending on which page you're on, and may be missing some links that are present on the sidebar of other pages.
Examples:
Actor classes: ZScript sidebar category is missing entirely.
Action functions: ZScript sidebar category is present, but is missing the "Reference" link.
I don't know much about website designing, but shouldn't it be possible to create single, shared sidebar to be referenced from all the pages?