XnView Software

BINGO!
I have one monitor, but windows detected two.
Helped change windows settings.

THX Marffy

I don't know, I probably need to reinstall Windows.

https://youtu.be/mqBOnAa1AE8

Marffy

After updating Windows 10 to version 1903, it is not possible to switch the image from the browser to the fullscreen display.
(From viewer it works)

Thanks for any idea.

Marffy

edit:
Deleting the INI or reinstalling the program was not enough.