Using glade 3.20.2-1 on Debian Testing amd64, all GtkImage share the same 
filename string, making all toolbuttons and other widgets using image to 
display the same image. Editing one GtkImage filename will make all other 
images to use this new filename.

This happens both when opening existing glade file or when creating a 
new glade project from scratch. For existing files, just opening a glade 
project makes all images share the same filename string.

This does not happen in glade 3.20.0-2 (Debian Stretch) and in other 
previous versions (on Debian Jessie).

Severity set to major since this does not allow me to work with glade 
anymore on my glade projects (this pervades all my images).

Please note that I just downloaded glade 3.21 and built it on my machine 
and the behavior is the same.