Canon EOS 80D - Manual (Page 206)

k Shooting Movies
204
 You can display the electronic level by pressing the <B> button
(p.66).
 Note that if the AF method is set to [u +Tracking] or the camera is
connected to a TV set with an HDMI cable, the electronic level cannot be
displayed.
 The electronic level, grid lines, or histogram cannot be displayed during
movie shooting. (The display will disappear when you start shooting a
movie.)
 When movie shooting starts, the movie shooting remaining time will
change to the elapsed time.