Since I had it on a few days back to connect to my phone, I turn it off, but next boot it is on again. MB is MSI Performance Gaming AMD Ryzen 1st and 2nd Gen AM4 M.2 USB 3 DDR4 HDMI Display Port Mini-ITX Motherboard (B450I GAMING Plus AC)
Disable the bluetooth autorun service. On KDE, it is in “System Settings” under “Startup and Shutdown”. Try searching for “startup” or “autorun” in start menu and see if you can find any kind of software for managing your startup services.
That’s a feature, not a bug. Set
cat /etc/bluetooth/main.conf | less -p AutoEnable
# AutoEnable defines option to enable all controllers when they are found. # This includes adapters present on start as well as adapters that are plugged # in later on. Defaults to 'true'. #AutoEnable=true