In order to move/pan the window by selecting the "Hand", you must also make sure that the mouse button is set to left, middle, or right. If no mouse button is activated, you cannot move.
The problem is only present on touch devices since these buttons are inactivated on other platforms.
Fixed in revision 27721.
Panning doesn't work at all for the moment, due to bug #4846 which this bug now depends on. Re-opening.
With bug 4940 the panning feature is disabled, this bug is thus invalid.
Reopening and moving away from 4.2.0 milestone. The fix in 27721 is still not verified.
Since Bug 4846 is fixed now, we can now verify this functionality, moving to current milestone.
Panning works fine now in the "no button" mode. Tested with Firefox on Android.