Comment 8 for bug 1411193

sorry; this is in fact what I meant:

I tried to enable bluetooth with the panel System/preferences/bluetooth (not with the indicator since I have no indicator);
so I switched to on the slider in the panel, and, immediately after this, I got the error message (in the notification panel).

I have no output for

dmesg | egrep 'btusb | ath3k'