[Dev-C++] Undocumented shortcut: feature or bug?

[<Luc...@wa...>]

Using 4.9.9.2 on several computers, I discovered accidentaly a shortcut 
(french azerty keyboards):
<Ctrl><Window><;>
Ctrl can be left or right or both
Window (the key with a desintegrating Window) can be left, right or both

When you press these keys at the same time, the current line is 
commented: two shashes added at the beginning of the current line, 
without moving the caret.
I did not find that shortcut in the help menu of the editor.

This shortcut is not really usefull (maybe a bug), but is there any 
other undocumented shortcuts?