Plain and simple, zooming or panning in 2019 CorelDraw leads to portions of the displayed object area to be blanked out. Zooming out and back restores this obvious display buffering failure... but as soon as the zoom in is done again, or a pan is done, then blank out..
Yes I have noticed this also. Very annoying. Only zooming out/back refreshes the screen. I can't believe nobody noticed this in Beta.
ctrl w. Just because it was noticed doe not mean it got fixed.
Then there's that!