When I switch from my single desktop monitor to my separate (not on my desk, but attached to the same PC obviously) other triple monitor setup, I have noticed that multiple program icons that are either in the visible system tray or up-arrow part, simply disappear. The programs remain opened, but their icon vanishes.
I do NOT use DF taskbars, and only have one taskbar on my triple monitor array.

When I switch back to my main desktop monitor, the icons return.
Any ideas how to fix?
Thanks!