Comment 12 for bug 1582496

Just received a similar message Ubuntu 16.04 using YAD (Yet Another Dialog):

(yad:8401): GLib-GObject-CRITICAL **: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

^^^ Appears about 20 times. I was in the process of adding new columns of icons to existing dialog box matching mime file types. Not sure exactly which code revisions caused the error though.