Allow users to zoom in on images such that one pixel in the JPEG (or full size RAW thumbnail) is one pixel on the back of the camera.
It's not exactly clear if Canon's image review for pictures presents a 1:1 magnification on the screen at the back but if it does, close this out. My feeling is that it doesn't but I might be wrong.
http://wiki.magiclantern.fm/userguide#play_mode_shortcuts
Please read the documentation, FAQ and search the forums before making any more duplicate feature requests.