Thanks for the find. The command you posted would be good for x86 only, one that would work across all archetectures and does the same thing is:
/usr/local/postinst/libgdk-pixbuf2.0-0 trigger
Since there is no telling how many packages might need this command, I have added it in sce-load along with commands to update gtk2 and gtk3 immodules. The 3 commands on my machine take a total of .14 seconds using the "time" command to measure. Not noticable and I have 2.8 GB of loaded files installed under /tmp/tcloop. The below has been added to sce-load to make sure the trigger commands are run if they exist.
if [ -e /usr/local/postinst/libgdk-pixbuf2.0-0 ]; then
sudo /usr/local/postinst/libgdk-pixbuf2.0-0 trigger > /dev/null 2>&1
fi
if [ -e /usr/local/postinst/libgtk2.0-0 ]; then
sudo /usr/local/postinst/libgtk2.0-0 trigger > /dev/null 2>&1
fi
if [ -e /usr/local/postinst/libgtk-3-0 ]; then
sudo /usr/local/postinst/libgtk-3-0 trigger > /dev/null 2>&1
fi
I have added this to sce-load and have posted a new RC.