2 monitors: one big one small. cannot place icons on big one

[Laszlo_Lebrun]

Dear community,
I freshly installed current version of Linux Mint on a notebook with a built-in screen of 1380*768.
Additionally I have attached an external full-HD 1980*1080 monitor and use both screens.

While the windows can be placed correctly on the full estate of my HD monitor, icons can only be placed in the 1380*768 corresponding place on the HD monitor's desktop.

Here apparently the greater resolution of the second external monitor is not used by the part of the desktop software responsible for icons placement.

If it is of some relevance, my graphics driver is GMA 3100X.

Thanks.
Laszlo