+The function <A HREF="node7.html#fn:WFrame.set_grattr"><TT>WFrame.set_grattr</TT></A> may be used to give frames
+(and their tabs) arbitrary extra attributes to be passed to the
+drawing engine. Hence, by configuring such substyles in the style
+configuration files, and turning on the attribute when needed,
+scripts may display visual cues related to the frame. There is
+also one extra attribute specially interpreted by the default
+drawing engine: the `<TT>numbered</TT>' attribute, which causes
+numbers to be displayed on the tabs.