After upgrading to Xubuntu 20.04, the xfce-4-panel and whiskermenu-plugin have a 1~ pixel gap at the bottom of the desktop
https://i.imgur.com/Kp9XHWm.png
After upgrading, it seems like whisker menu, and other plugins are properly fitting to the bottom of the screen (or any side). But the main panel isn't touching the sides of the desktop. Notice in the image the top and bottom of the panel aren't flushed with the whisker menu.
I've tried making a brand new panel and it has the same issue.
Is there any clarity on this issue? Thank you very much for your time.