Questions[shadow](ubuntu)

I cannot start my shadow pc. It starts up and acts like it will connect but then fails at the last moment with Error code: R-0x7F.

Attempts to fix the issue on my part:

1. Tried on android and ubuntu. Both the same issue.
2. Using the troubleshooting, tried shutting down the shadowpc and attempting to access again.
3. Using the troubleshooting, tried shutting down the shadowpc. Then attempted to start in safe mode using the safe mode option in troublshooting
4. I reset the shadowpc from my account web page.
5. Attempted steps recommended by Bot

I hope I have phrased this question correctly, it's a bit of an odd one.

I have an Ubuntu 18.04 host with many users on it. All of the users log into their account on the host via SSH public key. All accounts have no password. This means that the /etc/shadow entry for every user is !. (I do not mean to imply that any account has an empty password, which would mean anyone could enter a username and then hit Enter at the password prompt to log in. An account with no password and an account with an empty password are very different things!)

With this situation, users are unable to set a password for their account with passwd because changing your password requires entering the current one which they can't do. This is actually fine.

However, another thing they can't do is change their shell because doing this requires entering a password, which the accounts don't have.

One solution I found suggests replacing required with sufficient in this line in /etc/pam.d/cshs:

# This will not allow a user to change their shell unless
# their current one is listed in /etc/shells. This keeps
# accounts with special shells from changing them.
auth       required   pam_shells.so

This works but my concerns with this are:

1. I don't understand why this works in my case because users' shells are already in /etc/shells. So why does modifying this suddenly allow users to use chsh without a password? (To be clear, in all cases, the users' current shells and desired shells are both listed in /etc/shells.)
2. I don't necessarily want service accounts to be able to change their own service-specific shells although this isn't quite as important.

I feel like this is something than can be solved by PAM in a more elegant way, somehow.

Whenever I move my mouse, the window where the mouse is gets the focus. That's the only true way of a good windowing system!

Only the default theme takes like 0.5 to 1 second to switch between windows. I can see some animations with the stupid shadow and colors changing. Is there a way to suppress that animation and even the shadow?

I'm thinking that maybe I need to try other themes to resolve the issue. In that case, do you know of a theme which would not have those bells and whistles?

I'm using Xfce4 currently with Compiz, which I installed following my own workflow here.

After some changes to my desktop setup, I would like to add a shadow to the Xfce panel, but I've been unsuccessful so far.

Compiz is active and I can even change the shadow effects live in CCSM under Window Decorations. Adding and removing specific windows from both the decoration and the shadow effects also works, but even though both values are set to any and even when I specifically add | class=Xfce4-panel to them, the panel won't draw a shadow.

The command is specified as /usr/bin/gtk-window-decorator, even though I have installed Metacity for window decorations, but it appears to work this way, so I am not sure if that is correct or not.

I believe that there should be a rule somewhere that prevents shadows from being drawn by panels and such things as Firefox bookmark-popups. I remember that there was an option to specify this in Compton, but I don't know where to find it for Compiz or any other way to accomplish this.

Is there a way to add a shadow to the Xfce panel?

When looking into /etc/passwd and /etc/shadow I found many non human users. I read a bit about it and know what they do (as a group, though specifically I see many I have no clue about). All of them (excluding root (locked pwd) and my human user account) have never established passwords (*'s).

Are there any tests or things I can or should do to ensure these are not leaks and we can trust them.