Add a mailto choice to Internet Address

Fixes #11149

gramps/gui/editors/editlink.py

@@ -142,7 +142,8 @@ class EditLink(ManagedWindow):
     def update_ui(self, widget):
         url = self.url_link.get_text()
         # text needs to have 3 or more chars://and at least one char
-        match = re.match(r"\w{3,}://\w+", url)
+        # valid internet address are: http://, https://, ftp:// and mailto:
+        match = re.match(r"(\w{3,}://\w+|mailto:\w+)", url)
         if match:
             self.ok_button.set_sensitive(True)
         else: