The original consolekit was abandoned upstream several years ago. The new consolekit2 version is actively maintained though.

Yes, ConsoleKit2 is what I meant. Would be nice to see it make a comeback. :-)

Did you try just simply 'sudo synaptic'? That's what I have to do from the terminal in dwm on antiX to get synaptic running

pkexec should work just fine in antiX as long as consolekit is running. You probably haven't installed and autostarted a graphical authentication agent. Try installing the mate-polkit package then add this to your autostart file (~/.xsession?) before the exec dwm line:

/usr/lib/x86_64-linux-gnu/polkit-mate/polkit-mate-authentication-agent-1 &

The original consolekit was abandoned upstream several years ago. The new consolekit2 version is actively maintained though.

Did you try just simply 'sudo synaptic'? That's what I have to do from the terminal in dwm on antiX to get synaptic running. If I recall correctly, pkexec commands just spit out errors in that environment.

Yes, this works. But this bypasses the point of polkit.

This suggests that consolekit's DBus API is different and requires that software be built to support that instead of elogind.

Yes, I just figured this out so I restored my timeshift snapshot from before.

Well, elogind is extracted from systemd. I don't see why consolekit needed to be replaced, as distros I've tried that still use it (such as PCLinuxOS) work just fine, and since it was still in Devuans repositories (its not in Debians) I wanted to see if it would work. It doesn't, unless you rebuild any components that use the elogind flag.

Any particular reason why you've switched to consolekit?

When trying to run programs like synaptic-pkexec, I get the following error:

polkit-agent-helper-1: error response to PolicyKit daemon: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie
==== AUTHENTICATION FAILED ===
Error executing command as another user: Not authorized

This incident has been reported.

This is what /var/log/auth.log says:

Feb 11 11:46:01 B550M polkitd(authority=local): Registered Authentication Agent for unix-process:7893:242677 (system bus name :1.203 [pkexec /usr/sbin/synaptic], object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8)
Feb 11 11:46:03 B550M polkitd(authority=local): Operator of unix-process:7893:242677 FAILED to authenticate to gain authorization for action com.ubuntu.pkexec.synaptic for unix-process:7893:242677 [/bin/sh /usr/bin/synaptic-pkexec] (owned by unix-user:hunter)
Feb 11 11:46:03 B550M pkexec[7894]: hunter: Error executing command as another user: Not authorized [user=root] [TTY=/dev/pts/0] [CWD=/home/hunter] [COMMAND=/usr/sbin/synaptic]
Feb 11 11:46:03 B550M polkitd(authority=local): Unregistered Authentication Agent for unix-process:7893:242677 (system bus name :1.203, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8)

I've tried with both mate-polkit and gnome-polkit with the same result.