The file "extensions/actions/action-properties.glade" contains a tooltip for the
whole window, that is quite similar to the tooltip of the Name entry.

Perhaps this is a mistake. If not, use an identical tooltip for both please.

Window:
"The action name. If a character is preceded by an underscore, that character
will be used as the access key for the menu item."

Name entry:
"The action name. If a character is preceded by an underscore, that character
will be used as the accelerator key for the menu item."