Settings or Bug problem (texture painting with images/stencils)

In 2.79, and in 2.80/2.81/2.82 I have been able in the past to load an image as a paint brush, and then move/rotate/scale it while painting onto the surface of a model.

Now, it seems no matter what I do, the representation of the stencil image is stuck in the lower left corner of the window.
Is this a settings issue, or is there something not working properly?

the keys changed in 2.81

Right mouse button is grab, + shift = scale, + Ctrl = rotate

I have attempted with left, right, and middle to move the texture/stencil. I am able to get it to paint properly, I just can’t move the stencil from the corner.

(Please ignore the horrible model, it’s my first piece of furniture).

What I wrote above applies to the default setting. Maybe you accidentally changed the links. Sometimes addons overwrite certain shortcuts. You can restore the basic settings with File> Defaults> Load factory settings.