Quote:...When I try to move using Spacebar-left click combo something hangs. the computer becomes unresponsive. and no matter where I move the mouse, the pointer displays the "move" cross...
...and you are doing this in order to...what?
Usually it moves the canvas and spacebar on its own should be sufficient, no need to left-click.
I normally use Linux, but just given it a try in a Win10 VM with Gimp 2.8.20 and it works as expected. My advice is do not left-click just use the space bar on its own or use neither, try the move canvas tool bottom right as circled.
It could be a bug in Gimp, maybe some Win10 user will be able to reproduce it, but equally it could be a bug in Windows or a mouse (do you use a tablet?) issue.