SUMMARY
When I press Alt+Tab, hold Alt, then press Alt+Backtick (or vice versa), the tab box sometimes disappears, leaving just the highlighted window and the wallpaper.

STEPS TO REPRODUCE
1. Press Alt+Tab.
2. Wait for the focused window to be shown and other windows to vanish.
3. Release Tab, hold Alt, and press Backtick.
4. If the bug does not happen, continue alternating Tab and Backtick.

OBSERVED RESULT
The Alt+Tab UI disappears, leaving only a single window on the wallpaper. You can continue to press Tab or Backtick and it will work.
This applies even to effects like Cover Switch which cover the entire screen and do not highlight a single window on the wallpaper.

EXPECTED RESULT
The Alt+Tab UI remains visible.

SOFTWARE/OS VERSIONS
Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.19.0
Qt Version: 6.9.2
Kernel Version: 6.16.11-200.fc42.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 8 × Intel® Core™ i7-8559U CPU @ 2.70GHz
Memory: 16 GiB of RAM (15.5 GiB usable)
Graphics Processor: Intel® Iris® Plus Graphics 655
Manufacturer: Intel(R) Client Systems
Product Name: NUC8i7BEH
System Version: J72992-303

ADDITIONAL INFORMATION
Possibly related to Bug 454413, where switching keys focuses the window and causes kwin to *think* the Alt+Tab operation is over, and close the UI or fail to open/switch to the other UI?