Ubuntu supports Bluetooth very well, but the Bluetooth is automatically enabled every time it is started. Even if Bluetooth is disabled, it will be automatically turned on after the next restart of ubuntu, that is, UBUNTU will not record the Bluetooth status.
After reading some posts in the UBUNTU Forum, the solution is generally to disable Bluetooth management in the system> preferences> startup.Program. The result is that the Bluetooth manager is not started, but the Bluetooth indicator is still on, and the Bluetooth function is not actually disabled. Another method provided by a friend is to disable Bluetooth in the bios, so that it is very troublesome to enable it in the BIOS after restarting it when you want to use it.
My current practice is to keep the automatic start of the Bluetooth manager, and then disable the Bluetooth through configuration. If you want to use it, open it in the Bluetooth manager for convenience.
Sudo gedit/etc/rc. Local
Then, add the following line
Rfkill block Bluetooth
After the instance is restarted, Bluetooth is disabled by default.