I posted a bug on Wayland’s bugzilla page (http://bugs.freedesktop.org/show_bug.cgi?id=100740).
While running Blender 2.78c, Pressing G to move an object or Shift+F to enter fly mode, then moving your mouse to the edge of the viewport screen causes the viewport window to go berzerk: either the window orientation will go all over the place (if Shift+F) or the object you’re moving will go WAY off-screen (G+move mouse to viewport window’s edge).
Is anyone else experiencing this? Is there a work-around or fix?