Anyone who has suffered the indignity of a splinter, a blister, or a paper cut knows that small things can sometimes be hugely annoying. You aren’t going to die from any of these conditions, but it’s still hard to focus when, say, the back of your right foot is rubbing a new blister against the inside of your not-quite-broken-in-yet hiking boots.

I found myself in the computing version of this situation yesterday, when I was trying to work on a new Mac Mini and was brought up short by the fact that my third mouse button (that is, clicking on the scroll wheel) did nothing. This was odd, because I have for many years assigned this button to “Mission Control” on macOS—a feature that tiles every open window on your machine, making it quick and easy to switch apps. When I got the new Mini, I immediately added this to my settings. Boom!

And yet there I was, a couple hours later, clicking the middle mouse button by reflex and getting no result. This seemed quite odd—had I only imagined that I made the settings change? I made the alteration again in System Settings and went back to work.

But after a reboot later that day to install an OS update, I found that my shortcut setting for Mission Control had once again been wiped away. This wasn’t happening with any other settings changes, and it was strangely vexing.

When it happened a third time, I switched into full “research and destroy the problem” mode. One of my Ars colleagues commiserated with me, writing, “This kind of powerful-annoying stuff is just so common. I swear at least once every few months, some shortcut or whatever just stops working, and sometimes, after a week or so, it starts working again. No rhyme, reason, or apparent causality except that computers are just [unprintable expletives].”

But even if computers are [unprintable expletives], their problems have often been encountered and fixed by some other poor soul.