Disappearing task tray items

New to XFCE, used gnome and Windows a long time. Also have a script that fires xrandr on login bc the screen is portrait on this particular laptop. I can see an app (let’s say Manjaro-Hello) is running and has a PID through Task Manager. But no sign of that app anywhere but TM, I see a stack of items running in a small “virtual desktop” to the left of the quick launch but they are foreground/background, and the background items don’t include, e.g., Manjaro-Hello that I see running in TM. Any chance the problem has to do with XFCE not handling the xrandr correctly when it paints the taskbar items? Or is it just me making some dumb rookie overlook? The “getting started” pages in xfce.org really don’t correspond in appearance to my Manjaro Xfce variant. For example, quick launch is on the lower left “start” button, not in the middle of the lower bar in large icons.
–“Dorothy, you’re not in Redmond any more”