In x86 64 bit TC (versions 11.1 and 12.0) the icon for evince.tcz is duplicated in wbar after reboot. That is, after downloading and installing evince.tcz a single evince icon appears in wbar, but upon reboot the icon appears twice. Subsequent reboots have the same two icons. This happens on my desktop and laptop.
Maybe this is an evince problem and not a wbar one? Both icons work!
Thane