Stack Exchange has many sites with similar themes, such as Math Stack Exchange vs MathOverflow or Super User vs Ask Ubuntu. I find it fairly difficult to find what is relevant on a particular Stack Exchange site. Only in doing research for this question did I discover that there exists a "/help/on-topic" page for each site that a user can access by going to "?" > "Help Center" > "What topics can I ask about here?".
In particular, I am perpetually surprised that this isn't part of the tour. The tour bills itself as "a quick overview of the site" but is actually a description of how Stack Exchange in general works and has almost nothing about the specific site itself.
Can we put a link to "/help/on-topic" in the tour?
Note: my complaint is similar to that here Drawing more attention to */help/on-topic on the "Ask Question" page but my proposed solution is different.