Glade for GTK-2.x is not available in current Debian / Ubuntu distributions (since Glade 3.10 only GTK-3.0 is supported). But we can build it from source, see here.

So, how to build Glade 3.8 for GTK 2.24 ?

git clone https://gitlab.gnome.org/GNOME/glade.git
cd glade && git checkout GLADE_3_8_6 # last version for GTK-2.x
./autogen.sh
./configure
make
sudo make install
sudo ldconfig