Tags: patch This was a hard one to find... The problem is in gtkutil.c xg_show_tooltip: gtk_widget_show_all makes the icon that comes by default with a tooltip visible, which is undesirable since that icon was never set. The fix is to simply use gtk_widget_show. Attached is a python script that reproduces the behavior, trying to mimic the real emacs code. The first time you press the button show is called and the tooltip has no icon, as expected. The second time show_all is called and the missing icon problem manifests. If you keep pressing the button show and show_all alternate, but the missing icon is still there since it has been made visible forever by the first show_all call.