[cornedor]

> I'm guessing that at nine nines that is pretty much a one anyway and it would not even change a single pixel on the screen.

There used to be a bug with flex-wrap: wrap; where an element would wrap to the next line while it should have fit. You could fix it by instead using width: 25%; use width: 24.999999%; so it would be 25% on the screen but it would fix the problem so it didn't wrap to the next line. So you should look out with this.

[b34r]

That sounds like the time-honored single whitespace bug. Usually fix it with margin-left: -4px on all but the first element in the row.

[remy_luisant]

Nice catch. Yeah, I do something like that too in my own code, though it does not cause issues when minified.