I was browsing the new tags page when I saw the tag se-bad-field. On clicking the tag it took me to the wiki page of it where it said there was already 1 question tagged with it. But as you can see in the right half of the screenshot, it wasn't displaying the question on any of the tabs.
You can see the question in the left half of the above screenshot. I only managed to open it by doing a quick F5+Esc combo! See screenshot:
I even turned off Ad-blocker just in case.