wayland clipboard copy on fullscreen window cause transient notification and window movement

[mcmahanp]

Describe the bug
When in a full-screen terminal window, using wl-copy directly (or another program like helix editor that apparently uses the same functionality) causes the whole window to shift downwards very briefly while a notification appears from "Unknown" saying "wl-clipboard is ready". The whole thing lasts less than 1/4 second (see attached video below)

To Reproduce
Steps to reproduce the behavior:

1. Open a terminal emulator (default gnome terminal works, also tested in kitty)
2. Switch to fullscreen in the hamburger menu in top right
3. Type wl-copy foo to copy "foo" to the clipboard

Expected behavior
No change in window positioning

Screenshots

copy_jitter_full.trimmed.mp4

System information:

Distribution: Ubuntu 24.04.3 LTS (Noble Numbat)
GNOME Shell: 46.0
Display server: Wayland
PaperWM version: 49.0.0
Enabled extensions:
- paperwm@paperwm.github.com
- appindicatorsupport@rgcjonas.gmail.com
- mediacontrols@cliffniff.github.com
- TeaTimer@zener.sbg.at
- transparent-top-bar@ftpix.com
- pomodoro@arun.codito.in

Additional context

This seems to be the general issue that is causing #1021

Trying the workaround in #466 (comment) (sending 'wl-clipboard' to scratch layer with winprops) stops the shaking window, but it makes the terminal lose focus. Even clicking in the terminal doesn't work -- you need to use super-esc a coupld of times to open and close the scratch layer (I assume).