Questions[gnome-screensaver](ubuntu)

I'm currently using a fork of Antergos web-greeter because I don't like the default. However I can't use the default screensaver because if I lock through that I can simply press Ctrl + Alt + F7 to circumvent the login and be back in my session (the web-greeter runs on tty8). This is a big problem which I was able to solve by using light-locker. This worked fine until I upgraded to 20.04. Now light-locker won't start because gsd-screensaver-proxy is already running. I tried to solve that by setting the value in org.gnome.settings-daemon.plugins.screensaver-proxy to false. That didn't work. Does anyone know how I can either stop gsd-screensaver-proxy from starting automatically and how to use light-locker instead? I would also be happy if there is a way to ditch light-locker completely and use the default instead.

In shortcuts i have Super + L for locking screen. But on pressing it - nothing happens. In syslog:

gsd-media-keys[1979]: Couldn't lock screen: Cannot invoke method; 
proxy is for the well-known name org.gnome.ScreenSaver without an owner, and proxy was constructed with the G_DBUS_PROXY_FLAGS_DO_NOT_AUTO_START flag

Locking from interface works fine.

System info: Ubuntu 19.04 upgraded to 20.04

Linux laptop 5.4.0-21-generic #25-Ubuntu SMP Sat Mar 28 13:10:28 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 20.04 LTS
Release:    20.04
Codename:   focal

GNOME Shell 3.36.1

Other info:

gsettings get org.gnome.desktop.screensaver lock-enabled = true
gsettings get org.gnome.desktop.lockdown disable-lock-screen = false

gnome-screensaver 3.6.1

I also tried: gnome-screensaver-command -l but nothing happens.

I already tried to reinstall gnome-shell and gnome-screensaver - it didn't help.

How to fix locking screen from hotkey?

Ubuntu doesn't ask for my password when I'm getting out of sleep when closing my laptop and reopening it. I've followed everything listed here : Ubuntu 17.04 no longer asking for password when coming out of sleep mode but it keeps not asking my password. Moreover, the command Super + L doesn't lock the screen either. You can find below screens of my settings ( in french, sorry, but it shouldn't be difficult to understand what it corresponds to. So the options for automatic lock of the screen and locking screen when in sleep mode are activated, and the delay for locking the scren is " when screen shuts" )

Moreover, you can see here that the command

gsettings get org.gnome.desktop.screensaver ubuntu-lock-on-suspend

gives true, and

gsettings get org.gnome.desktop.lockdown disable-lock-screen

gives false.

It could be related to issues I had some time ago with i3 that wasn't asking either for a password when getting into sleep mode. I remember that I tried different manips but can't remember the details. I've already removed i3 totally.

Could someone help me please ?

I received this critical error in my logs, but I haven't had any problems so far. If anyone knows why I get this error and what it means, I'd really appreciate an answer from you.

CRITICAL: Unable to create a DBus proxy for GnomeScreensaver: Error calling StartServiceByName for org.gnome.ScreenSaver: GDBus.Error:org.freedesktop.DBus.Error.Spawn.ChildExited: Process org.gnome.ScreenSaver exited with status 1

How to change the settings to the screen locker not to mute the sound while the screen is locked?