Screenshot app not working
In Mojave Grab has been replaced by Screenshot. The app is dysfunctional. After the image is obtained the selection box remains on the screen with the rest of the screen greyed out. The only solution I found was to restart, force quit does not solve the problem. The other solution is to use command-shift-4 which uses a different process to selection part of the screen.
If there is another solution I would like to know, otherwise I think there is some debugging work to be done by Apple.
MacBook Air, macOS Mojave (10.14.1)