When styling a form element in Bootstrap 3, it renders an ugly button on the in Firefox on OS X:
This is the normal behavior, and it's caused by the default style under Firefox : you can't set line-height, then you need to play on padding when you want to have a customized .
line-height
padding
Example, with results under Firefox 25 / Chrome 31 / IE 10 :
Default Default Default Bootstrap Bootstrap Bootstrap Custom Custom Custom
select.custom { padding: 0px; }
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