Ubuntu 15.10 and GTK: getting new errors and warnings after failed attempt to install pygtk -- unable to resolve even after re-installation of gtk and glibc

[Brian Merchant <bhmerchant gmail com>]

Hi all,

I am quite suddenly getting the following gtk warnings whenever I run any Python program (e.g. matplotlib, pyqt5, etc.) that cause a GUI window to appear:

GLib-GIO-Message: Using the 'memory' GSettings backend.  Your settings will not be saved or shared with other applications.
    
(python:3369): Gtk-WARNING **: GModule (/usr/lib/x86_64-linux-gnu/gtk-2.0/2.10.0/immodules/im-ibus.so) initialization check failed: GLib version too old (micro mismatch)
    
(python:3369): Gtk-WARNING **: Loading IM context type 'ibus' failed

Normally, since they are warnings, I would not have been worried since perhaps a recent update may have caused them to suddenly appear (they began appearing yesterday, after my unsuccessful attempt to install pygtk). However, this also seems to more generally be a serious issue, because for instance, if I make a PyQt5 skeleton app, I get the following error if the app uses the default window style, "gtk+":

(python:1949): Gtk-CRITICAL **: IA__gtk_widget_style_get: assertion 'GTK_IS_WIDGET (widget)' failed
QWidget::setMinimumSize: (/Editor) The largest allowed size is (16777215,16777215)

Actually, under certain conditions, this can cause my entire computer to crash, which is really bad. Others, also on Ubuntu, have tested my code out and do not have this problem.

In order to fix whatever issues I might have inadvertently caused, I attempted the following:

1) reinstalling gtk2+ and gtk3+ (libglibc a dependency) along with all their dependencies

2) reinstalling ubuntu-desktop and its dependencies

3) reinstalling ubuntu entirely (while still preserving my home directory, so, non-destructive re-install)

However, I am still having the issue. Your help would be much appreciated!

Kind regards,

Brian