I'm reporting a recurring issue when starting Synaptic and Gparted (it seems to happen every time with Synaptic, and every time after the first in a given login session with Gparted), apparently related to Polkit / pkexec. Both of these applications require root access, and use pkexec to get that (via /usr/bin/synaptic-pkexec for Synaptic and /usr/sbin/gparted for Gparted). When launching the application, the pkexec password box appears but instantly freezes, then shakes and says "Authentication failed. Please try again." This is before I type anything into the password dialog! After this I can enter my password and everything works as expected.
Conversely, when I open root instances of the file manager or terminal using Polkit actions I've set up (for right-clicking within the file manager... I've set these up for both io.elementary.files and PCManFM), they work fine... and I can't see anything substantially different between these action files and the pre-existing Polkit action files for Synaptic and Gparted.
Below is some information from /var/log/auth.log showing what's logged when the problem happens (and it's the exact same message that's logged if I enter an incorrect password):
May 1 23:45:57 E7250 polkit-agent-helper-1: pam_unix(polkit-1:auth): authentication failure; logname= uid=1000 euid=0 tty= ruser=sillyrat rhost= user=sillyrat
For Gparted (it's basically identical to the message for Synaptic):
May 1 23:45:16 E7250 polkit-agent-helper-1: pam_unix(polkit-1:auth): authentication failure; logname= uid=1000 euid=0 tty= ruser=sillyrat rhost= user=sillyrat
I've gone as far as I personally am able with troubleshooting this annoyance... any ideas? Thanks for your input!