External monitor setup - 'Offloading Graphics Display'

Hi,
I’m ruuning Linux Mint 20 Cinnamon with Geforce RTX 2060 “On Demand” mode and recently updated to nvidia-driver 450.57. Thanks to new LM 20 I can choose run some aplications using NVIDIA GPU. I didn’t change any config file or setting to run ‘Offloading Graphics Display’ that allows me conect a HDMI external monitor.

But I have an issue: in my dual monitor setup I have notebook below and external monitor above. I use the Panel on top of notebook screen. I can’t drag/move any window up to external monitor. And nothing happens when use window command ‘Move to the other monitor’. It seems that Panel is literally blocking this action. It does not happen if I configure the monitor in other positions (below or right/left side) or if I move Panel to bottom, left or right (then I can move any window freely). I tried create and edit with xorg.conf after reading the documentation but without success. I believe that LM20 manage config files at /usr/share/X11/xorg.conf.d

Any help?