This depends on the tab renderer being used for the CTabFolder
. For the standard I don't think you can change this.
Using the tab renderer used by Eclipse there are a number of values you can set:
CTabFolder
{
swt-tab-renderer: url('bundleclass://org.eclipse.e4.ui.workbench.renderers.swt/org.eclipse.e4.ui.workbench.renderers.swt.CTabRendering');
swt-unselected-tabs-color: white white white 100% 100%;
swt-selected-tab-fill: white;
swt-outer-keyline-color: white;
swt-tab-outline: white;
swt-shadow-visible: false;
swt-simple: true;
swt-tab-height: 22px;
swt-selected-tabs-background: white white 100%;
swt-shadow-color: white;
}
swt-tab-renderer
sets the tab renderer to be use.
I think swt-tab-outline
sets the tab outline, but you may have to play with the others to get something consistent.