This error appears if trying to open appmenu on panel by shortcut, assigned to xfce4-popup-applicationsmenu. First time. Second time it opens, but from desktop. However, launching xfce4-popup-applicationsmenu from command line works at least if menu was opened before. If it failed before, as first time, it will open from desktop too. Exact message: (xfce4-panel:17286): Gtk-WARNING **: no trigger event for menu popup
Having exactly the same issue. When activating the keyboard shortcut, the applications menu darkens as if pressed but the menu itself doesn't popup. I had no xfdesktop and an error appeared in .xsession-errors because of that, but after installing xfdesktop the only difference is that the second time the keyboard shortcut is activated, the desktop menu pops up. Diff in .xsession-errors is $ diff .xsession-errors-1 .xsession-errors-2 11a12,15 > > (xfce4-panel:869): Gtk-WARNING **: 16:23:12.196: no trigger event for menu popup > > (xfce4-panel:869): GLib-GObject-CRITICAL **: 16:23:12.197: g_object_set_data: assertion 'G_IS_OBJECT (object)' failed Fedora 30, xfce4-panel-4.13.5-1.fc30
Oh well... now is working. If I remember well, just when I installed this system (yesterday), it did work somewhat. Actually everything had some visual glitches, but then this particular keyboard shortcut stopped working once and for all... until now. The only thing I did that mysteriously (I'm not a coder, so most things are like that for me) may have influenced is that I changed settings in xfconf gui (unrelated lock screen settings). Let's see if it will still work after a reboot or logout.
Not working any more. I'll stop spamming now.
This issue was already reported. *** This bug has been marked as a duplicate of bug 14892 ***