$ dpkg -l libgtk* | grep -e '^i' | grep -e 'libgtk-*[0-9]'
ii libgtk-3-0:amd64 3.22.30-1ubuntu4 amd64 GTK+ graphical user interface library
ii libgtk-3-bin 3.22.30-1ubuntu4 amd64 programs for the GTK+ graphical user interface library
ii libgtk-3-common 3.22.30-1ubuntu4 all common files for the GTK+ graphical user interface library
ii libgtk2-gladexml-perl 1.007-2build4 amd64 Perl interface to use user interfaces created with glade-2
ii libgtk2-perl 2:1.24992-1build1 amd64 Perl interface to the 2.x series of the Gimp Toolkit library
ii libgtk2.0-0:amd64 2.24.32-1ubuntu1 amd64 GTK+ graphical user interface library
ii libgtk2.0-0:i386 2.24.32-1ubuntu1 i386 GTK+ graphical user interface library
ii libgtk2.0-bin 2.24.32-1ubuntu1 amd64 programs for the GTK+ graphical user interface library
ii libgtk2.0-cil 2.12.40-2 amd64 CLI binding for the GTK+ toolkit 2.12
ii libgtk2.0-common 2.24.32-1ubuntu1 all common files for the GTK+ graphical user interface library
ii libgtk3-perl 0.032-1 all Perl bindings for the GTK+ graphical user interface library
**Firefox**: I seem to remember that, a year or two ago, it used to happen with Firefox; but, after some time (some months?) the problem disappeared. I do not have it now.
**GTK**: I am unsure. Does the following help?
$ dpkg -l libgtk* | grep -e '^i' | grep -e 'libgtk-*[0-9]' gladexml- perl 1.007-2build4 amd64 Perl interface to use user interfaces created with glade-2
ii libgtk-3-0:amd64 3.22.30-1ubuntu4 amd64 GTK+ graphical user interface library
ii libgtk-3-bin 3.22.30-1ubuntu4 amd64 programs for the GTK+ graphical user interface library
ii libgtk-3-common 3.22.30-1ubuntu4 all common files for the GTK+ graphical user interface library
ii libgtk2-
ii libgtk2-perl 2:1.24992-1build1 amd64 Perl interface to the 2.x series of the Gimp Toolkit library
ii libgtk2.0-0:amd64 2.24.32-1ubuntu1 amd64 GTK+ graphical user interface library
ii libgtk2.0-0:i386 2.24.32-1ubuntu1 i386 GTK+ graphical user interface library
ii libgtk2.0-bin 2.24.32-1ubuntu1 amd64 programs for the GTK+ graphical user interface library
ii libgtk2.0-cil 2.12.40-2 amd64 CLI binding for the GTK+ toolkit 2.12
ii libgtk2.0-common 2.24.32-1ubuntu1 all common files for the GTK+ graphical user interface library
ii libgtk3-perl 0.032-1 all Perl bindings for the GTK+ graphical user interface library
**Firefox**: I seem to remember that, a year or two ago, it used to happen with Firefox; but, after some time (some months?) the problem disappeared. I do not have it now.