style.css - Original File
.box { -webkit-border-radius:8px; -moz-border-radius:8px; padding:10px; }
style.css - In Firebug CSS Console
.box { -moz-border-radius:8px 8px 8px 8px; padding:10px; }
How can I force Firebug to show my -webkit css styles as well? Thanks for your help!
I don't think you can - the correct behaviour for browsers is to ignore style rules they don't understand. Firefox sees -webkit-xxx and effectively removes it from the style set, so it can't ever be applied to .box.
Safari's inspector will show the -webkit- rules but ignore the -moz- rules for the same reason.
Firebug handles only Gecko's native rules (styles). Gecko is a browser engine, used in Firefox (http://ru.wikipedia.org/wiki/Gecko).
-webkit is used by another browser engine, so it is ignored.
similar to -ms ("Trident" engine - IE8), -o (Presto - Opera), or -khtml (KHTML - Konqueror).
来源：https://stackoverflow.com/questions/2808146/firebug-kills-webkit-settings-in-css-file-why