OK, experts.  Here’s an “I don’t know what I don’t know” issue.
Today, I set up a second monitor on my two year old VR capable W10 PC equipped with a 1070 graphics card.  The #2 monitor is plugged into a display port on the 1070 card.  I went into the W10 settings and established the newly installed monitor as #2.  The #2 monitor is showing the same desktop photo as the #1.  I can freely move the mouse cursor and any desktop icon back and forth between the two monitors.  But, when in game, I can’t move anything (clipboard or radio box) beyond the screen margin of the #1 monitor.  A while back, a friend told me he set up a second monitor so he could display the clipboard and radios box on the it to free up space on the #1 display and he was able to do so.  That sounded like a good idea so, I set up the second monitor today.  Any idea what I’m doing wrong?  Thanks!