Aisleriot toolbar icon spacing with gtk3 - possible bug?

[golinux <golinux riseup net>]

I am using Xfce DE version 4.10 on Debian Jessie.  I am re-colorizing 
the Xfce window theme (/gtk-2.0/gtkrc and /gtk3.0/gtk.css) and found a 
possible bug with the Aisleriot toolbar icon spacing.  Note that I have 
only switched out colors - not mucked around with any of the underlying 
code. The gtk-3.0 was ported from gtk-2.0 by Peter de Ridder.  My email 
to him has gone unanswered.

The toolbar displays as it always has with gtk2 (gtk2.png) but with gtk3 
(gtk3.png and gtk.css) the icon spacing is ignored. It is unclear 
whether the problem lies there or with Aisleriot's gtk3 compatibility.   
EVERY Xfce gtk3 compatible theme in /usr/share/themes displays this 
quirk and it is also happening to a lesser extent on Albatross and 
Greybird Mac.  Any thoughts about how to track this down would be 
appreciated.  TIA.

golinux

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