Yeah, looks like that’s it. The issue was compounded by the fact that I noticed this while I was adding a custom button for the RSS to the menu, and had part of the URL wrong. So I first was having issues because I was clicking a button to an incorrect URL, but was getting completely different responses from different computers and browsers.
Anyway, problem solved. Ish.
Ah, I figured out a sticky system. Normal sticky didn’t work, so I downloaded the WP-Sticky plugin. Its “sticky” setting didn’t work but its “announcement” setting did.