Upgraded operating system: Screenshots now only Wallpaper
So I've just upgraded my Macbook Pro to the new operating system. Now screenshot function has changed. All screenshots, or even if I do screen clipping, only take a picture of the wallpaper!?!?!?! How do I undo this, please? and the pictures are saved as /HEIC. Why, oh, why do developers change something that works and frustrate busy business people?