[Gimp-user] Rotating the entire frame of reference

[Jeffery Small <jeff cjsa com>]

GIMP 2.10.30 on Xubuntu 20.04

While performing other operations, I have found that the entire frame of
reference for gimp (image, guides, etc.) is rotated by holding Shift-B2
(middle mouse button) and dragging the mouse.  This always happens
accidentally and I have found no way to reset the view back to normal.
Here are my questions:

1: Is this type of rotation documented in the manual?
2: Why would you want to do this?  When you save the "rotated" image it
seems to be the same as "non-rotated".
3: Is there any way to reset the view back to the normal exactly orthogonal
position?
4: Is there a way to disable the Shift-B2 assignment so that this doesn't
happen?

Thanks.