Here is an example of it happening: https://jsfiddle.net/dgo3tfpv/1/
All mirror elements are added to the same wrapper, and the ! char of the second instance gets placed all the way on the right. That causes the span to have an incorrect width.

A possible fix is to set display: inline-block; on the spans.
Here is an example of it happening: https://jsfiddle.net/dgo3tfpv/1/
All mirror elements are added to the same wrapper, and the
!char of the second instance gets placed all the way on the right. That causes the span to have an incorrect width.A possible fix is to set
display: inline-block;on the spans.