This is a "feature" :). Although the tab widget is resized automatically, 
this doesn't seem to happen as often as is needed. It also seems to be 
mainly a feature of the X redisplay. It is also probably related to the 
problem Charles Waldman is seeing. I am investigating, but it takes time 
and crashes are always higher priority.
Its not a separator BTW - it is the bottom edge of the widget.
andy
At 02:23 PM 11/25/00 +0100, Bjorn torkelsson wrote:
Andy Piper <andy(a)xemacs.org> writes:
 > Well, this fixes the tab display oddities that Marcus and Stephen were
 > seeing. It took a long time to figure out, so I'm not sure how
 > worthwhile it was ...
There are still some artifacts with the gutter tabs :-(
Recipie:
xemacs -vanilla
resize the window (make it wider)
    The separator is not drawn all the way.
load a file - it looks ok.
load another file
resize again (make the window even wider)
    Same thing again
Switch between the the two buffers by clicking the tabs.
    There is a white "box".
Load a third file - everything looks ok again.
Switch between two the two first buffers with C-x b
     One of the two tabs are not drawn correctly
 
--------------------------------------------------------------
Dr Andy Piper
Principal Consultant, BEA Systems Ltd