Step to reproduce : change the color of the note

close/reopen note

watch the CPU usage spike to 90+ % and my laptop ventilation going crazy !
See the abrupt CPU usage down on the left of the image ?
that's when I kill Xfce Note

See the CPU usage spike on the right of the image and crumbling down ?
that's when I relaunch Xfce note and kill it.

It seems the only workaround is to NOT use this application, ever.
Just removed it from startup and will use my NextCloud Carnet instead !