Menus appear to the left of cursor

I recently had an odd behaviour on my SurfacePro4. I’m sure this only started happening after a recent automatic update… thanks Windows10 & Microsoft!
If you start getting this in your applications, then I suggest you follow these steps to resolve it.

The following works on Windows 10:

  1. Press the Windows logo key+R to bring up the Run dialog box. In the Open line, copy/paste the following text:
  2. Press OK
  3. This will start the Tablet PC Settings configuration dialog (Even if you do not have a Tablet PC).Select the Other Tab.In the Handedness section, place a check mark in the Left Handed option.
  4. Click OK.