Does not reproduce for me:

I did this on mobile. On mobile, there's no way to display this tooltips unless you click it.
But if you click it, it will go to the PR's page. And when you back to this page, you will see network error.
So I did two things together: show the tooltips (a bit faster) and go to the PR's page.
So for mobile view, maybe we need to allow user click a URL to show the tooltip at the first time if it has a tooltip, then the second time the click will go to the target link.

I can follow. When you click a link, it starts loading, but aborts because the page unloads. When you hit the back button, you get a cached page from bfcache which apparently also caches the error popup.

As for solutions, I think we could try to cancel the request before page unload and not show a error in such a case.

When you click a link, it starts loading, but aborts because the page unloads.

Yes, that's it. 👍

#31181 will fix this and other problems with that popup.