Why are the twitter-bootstrap styles for button set to overflow:visible?

Question

Why are the twitter-bootstrap styles for button set to overflow:visible?

Like this:

button{
  overflow:visible;
}

Answer 1

It belongs to Normalize.css not twitter bootstrap. It is used to reset the value of overflow to visible as it is set to hidden in IE 8/9/10/11 by default.

//
// Address `overflow` set to `hidden` in IE 8/9/10/11.
//

button {
  overflow: visible;
}