I use the default panel
- bottom
- stretches to the sides / "fill width"
- some widgets
- nonfloating

and a secondary one (the creation was really buggy, already reported)
- position right bottom
- dodge windows
- fit content

this secondary panel gets spawned aligned to the very bottom right, not "seeing" the "fill width" main panel.

The main panel thus covers it. After editing the panel edit mode on either one of the panels, the alignment is correct and they dont overlap.

But when restarting the session or using "kill plasmashell", this is reproducible and the main panel covers the secondary one again.

There is some issue with panels detecting other panels, and "fill width" panels should have priority over flexible panels, as these will always be there, not depending on other panels.

Operating System: Fedora Linux 40 Kinoite
KDE Plasma Version: 6.0.4
KDE Frameworks Version: 6.1.0
Qt Version: 6.7.0
Kernel Version: 6.8.9-300.fc40.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 8 × 11th Gen Intel® Core™ i7-1165G7 @ 2.80GHz
Memory: 15.5 GiB of RAM
Graphics Processor: Mesa Intel® Xe Graphics