… group name.
The gradient editor submenu add 2 submenus with changing names. It was using
again bogus actions: "gradient-editor-blending-func" and
"gradient-editor-coloring-type" do nothing except for being used as name
holders.
Instead I add the concept of group name for GimpRadioAction-s and when I use a
radio action attribute as <submenu>, this submenu will use the group name (and
sync with it, if it changes).
Jehan