https://bugs.gentoo.org/977206
https://sourceforge.net/p/mcomix/bugs/154/
https://sourceforge.net/p/mcomix/git/merge-requests/56/
https://sourceforge.net/p/mcomix/git/ci/274e95ecbcf1cdac6e26341bd7241dd86b70b417/

--- a/mcomix/keybindings.py
+++ b/mcomix/keybindings.py
@@ -176,7 +176,7 @@
         # Load stored keybindings, or fall back to passed arguments
         keycodes = self._action_to_bindings[name]
         if keycodes == []:
-            keycodes = [Gtk.accelerator_parse(binding) for binding in bindings ]
+            keycodes = [tuple(Gtk.accelerator_parse(binding)) for binding in bindings]
 
         for keycode in keycodes:
             if keycode in list(self._binding_to_action.keys()):
@@ -207,7 +207,7 @@
         """
         assert name in BINDING_INFO, "'%s' isn't a valid keyboard action." % name
 
-        nb = Gtk.accelerator_parse(new_binding)
+        nb = tuple(Gtk.accelerator_parse(new_binding))
         old_action_with_nb = self._binding_to_action.get(nb)
         if old_action_with_nb is not None:
             # The new key is already bound to an action, erase the action
@@ -216,7 +216,7 @@
 
         if old_binding and name != old_action_with_nb:
             # The action already had a key that is now being replaced
-            ob = Gtk.accelerator_parse(old_binding)
+            ob = tuple(Gtk.accelerator_parse(old_binding))
             self._binding_to_action[nb] = name
 
             # Remove action bound to the key.
@@ -238,7 +238,7 @@
         """ Remove binding for an action """
         assert name in BINDING_INFO, "'%s' isn't a valid keyboard action." % name
 
-        ob = Gtk.accelerator_parse(binding)
+        ob = tuple(Gtk.accelerator_parse(binding))
         self._action_to_bindings[name].remove(ob)
         self._binding_to_action.pop(ob)
 
@@ -299,7 +299,7 @@
         for action in BINDING_INFO.keys():
             if action in stored_action_bindings:
                 bindings = [
-                    Gtk.accelerator_parse(keyname)
+                    tuple(Gtk.accelerator_parse(keyname))
                     for keyname in stored_action_bindings[action] ]
                 self._action_to_bindings[action] = bindings
                 for binding in bindings: