Dell P2416D display blinks/blanks out (turns off and back on again)

If you’re using the USB hub built into the display, try disconnecting it (and all the USB cables connected to the display) and see if the issue still remains.

(This may not be a guaranteed fix for you, but for my display it seems to be, so I’m writing this down for myself, so that Google will find it when I again make the mistake of trying to use the USB hub and then wonder what the hell is causing my display to switch off and back on again.)