SUMMARY
With a panel on the bottom side of the screen clicks sometimes don't register, so for example opening pinned apps doesn't work, or clicking a virtual desktop on the pager does nothing. If I make sure not to have the mouse touch the edge then everything works as it should.

Hovering is also unreliable, although it alternates between working and not quickly enough so that only shows up when hovering over the pager while slowly moving the mouse diagonally downwards so the mouse constantly rubs against the edge the panel is attached to. Attached is a screen recording of the effect (although while the cursor blinks in the recording in reality the cursor just bounces up and down by 1 pixel).

The issue also occurs if I move the panel to the right side of the screen (so the issue appears when pushing the mouse against the right edge of the screen), but if the panel is at the top or on the left side the issue does not appear.


STEPS TO REPRODUCE
1. Have a panel on the bottom edge
2. Have a pager widget/plasmoid on that panel plus at least two virtual desktops
3. Slowly hover over the pager while keeping the cursor on the bottom edge of the screen

OBSERVED RESULT
The virtual desktop being hovered over blinks repeatedly.

EXPECTED RESULT
The virtual desktop being hovered over does not blink.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.27.0
KDE Frameworks Version: 5.103.0
Qt Version: 5.15.8
Kernel Version: 6.1.12-arch1-1 (64-bit)
Graphics Platform: Wayland

ADDITIONAL INFORMATION
The issue started occurring after upgrading to 5.27, although initially I just thought it was something on my end. Also, there is a report of a similar issue in the KDE subreddit: https://www.reddit.com/r/kde/comments/115vchq/lowest_pixel_zone_is_unclickable/