The bluetooth apple magic mouse (hid_magicmouse) disconnects from time to time,
the lower the battery the more often, and reconnects after around 15 seconds.
Rebuild the kernel with CONFIG_HID_BATTERY_STRENGTH=N and the issue disappears,
along with battery status reporting (which otherwise works and can be seen in gnome-shell power control panel).
I've seen this bug since the first introduction of CONFIG_HID_BATTERY_STRENGTH, but it wasn't that of a problem since that config has been off by default until recently.
Created attachment 203871 [details]
Patch from which a patch is proposed (serves as reference)
Created attachment 203881 [details]
Patch to disable magicmouse battery report support
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