Despite much googling I've still not resolved this and it's driving me nuts!

I have a DELL U2415 24" monitor. If I switch it off with the button at bottom right and back on again, all windows sizes and positions have been lost. They are then in some 'standard'-looking layout that would probably fit a smaller screen than my 1920 x 1200.

I've also raised it earlier in the DELL forum but so far no reply and email contact is apparently not possible.

I recall raising the same problem in the DELL forum about two years ago, but cannot locate it now. And anyway it was never resolved there. Obviously I somehow got it resolved later, but here it is again ;-(

Help on fixing this would be warmly appreciated please.

Version 1909 (OS Build 18363.1411) - 'up to date'.