VR Fix for Windows 10 Update

Windows 10 v1903 update prevents games from running in classic fullscreen

Some "fix" from Micro$oft causes issues in VR. Something to do with them trying to make their OS more intra-compatible with the XBox. or whatever. 

If you don't have one of these reg lines in "HKEY_CURRENT_USER\System\GameConfigStore" you need to make one.

This is done by right clicking in the open area of that list and you'll get "New >"

From the drop-down select "DWORD (32-bit) Value". 

Then right click and Modify the new entry with the name and value of the missing thingy (for example the one I had missing was "GameDVR_FSEBehavior") NOTE: The article has the word "behaviour" written in British English. Make sure what you name this is the same as your system. 104th Mustang, a Brit, has his in American English, as such:

Mustang's reg key

You want yours to look like this (specific order not withstanding if you had to add one like I did). 

Restart for reg edit changes to take effect. Be prepared for a long first boot of DCS (and probably a Not Responding or two).