In order to display rounded tabs (instead of rectangles), we just copied the complete ext.headertabs.bare.css (replaced bare with round) and added a section at bottom of the css.
#headertabs.round .ui-corner-top {
-moz-border-radius-topleft: 3px;
-webkit-border-top-left-radius: 3px;
-moz-border-radius-topright: 3px;
-webkit-border-top-right-radius: 3px;
border-top-left-radius: 3px 3px;
border-top-right-radius: 3px 3px;
}
#headertabs.round .ui-state-default, .ui-widget-content .ui-state-default, .ui-widget-header .ui-state-default {
border: 1px solid #DDD;
font-weight: normal;
color: #2779AA;
}
by MWJames
This post was posted by Ofbeaton, but signed as Olivier Beaton.