I have a bluetooth headset that was already paired from my PC user account. When I power on the headset, it automatically connects to my PC if PC was the last device it was connected to. Headset has a sound indication of connection/disconnection. The problem is that if I turn on the headset right after PC boot, headset automatically connects to PC even before login to user account from SDDM. What's even worse is that you can't disconnect the headset from login screen to connect it to another device (imagine if you're not the user and you don't know the password but want to use headset paired to this PC). Connection status is not displayed either, so it may be not obvious to which device headset is connected right now. After login, however, headset automatically disconnects for some reason and not reconnects again. Same applies to lock screen too - you can't see connection status and disconnect the headset if you're not the user and don't know the password. All said, there are 3 problems with bluetooth management from login and lock screens: 1. Bluetooth device can be autoconnected from login screen before login to user account and from lock screen 2. Bluetooth device connection status is not displayed on login and lock screens 3. Bluetooth device can't be disconnected from login and lock screens Besides, I don't know how Bluetooth manages keys, but isn't the autoconnection before login a vulnerability? Kubuntu 20.04.1 LTS with Plasma 5.18.5.
If you think about it, it may be useful to connect some devices automatically (or be able to connect them manually) from login screen such as bluetooth keyboard or mouse, for example if your main keyboard or touchpad are broken. Maybe other accessibility devices too.
Hmm, not sure how possible this would be.
Created attachment 132769 [details] Login/lockscreen info displayed in GDM/Gnome for comparison Tested it in Ubuntu 20.10 (with Gnome) just for comparison: 1. Gnome has an indication of the connected device on both login and lock screens - you can click on the top panel to see the name of the connected device. You can control the volume too. 2. The headset also connects before login and you cannot disconnect it - bluetooth button is not available on the panel. 3. The headset doesn't get disconnected after login, however the audio output is not automatically switched to the headset and there is no headset audio device in settings at all. So... Not sure about connecting/disconnecting (this is probably not a bug or broken by design), but I believe at least displaying more info on login/lockscreen can be done? Would be interesting to see how othes OSes deal with this (I don't have Windows or OS X available).
I see. Should be possible then.