For me, this is caused by disabling the plugin "Insert Date and Time".
Thanks to Jens, using "LD_PRELOAD=/usr/lib/libpeas-gtk-1.0.so.0 gedit" to open Gedit and change Preference to re-enable the plugin solved the problem. [Ubuntu 14.04.3 & Gedit 3.12.2] -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gedit in Ubuntu. https://bugs.launchpad.net/bugs/1325063 Title: Gedit preferences windows is empty Status in gedit package in Ubuntu: Confirmed Bug description: When I click the preferences item in menu I get a empty window that is just titled preferences. There is nothing in it and if I drag it to a bigger size an empty plane appears. When starting gedit as root I see the following error in terminal: (gedit:13564): Gtk-CRITICAL **: Error building template class 'GeditPreferencesDialog' for an instance of type 'GeditPreferencesDialog': Invalid object type `PeasGtkPluginManager' (gedit:13564): GLib-GIO-CRITICAL **: g_settings_bind_with_mapping: assertion 'G_IS_OBJECT (object)' failed (gedit:13564): GLib-GIO-CRITICAL **: g_settings_bind_with_mapping: assertion 'G_IS_OBJECT (object)' failed (gedit:13564): GLib-GIO-CRITICAL **: g_settings_bind_with_mapping: assertion 'G_IS_OBJECT (object)' failed ... UBUNTU 14.04, xsfc To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gedit/+bug/1325063/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp