Unable to select with which user to authenticate in gnome-authentication-agent-1

[Kosmas Ntouskos]

Hello,

Linking from the question I originally opened.
https://answers.launchpad.net/ubuntu/+question/698856

Apparently in the GUI it will only show a single sudo user to authenticate with, while pkexec will list all available sudoers.
This is for 18.04.

--QUOTE--
There are multiple users in the sudo group.
One user is bob and another user is tom. Both bob and tom are admins. Both are in the sudo group.

User kate is not an admin.
When kate tries to change the IP address, via the UI, she gets a prompt saying "System policy prevents modification of network settings for all users" and asks for bob's password in order to authenticate.
The problem is that kate does not have bob's password, she only has tom's password. However, in the ui, the gnome-authentication-agent-1, provides no way of changing bob to tom.

If kate tries to run a command via pkexec, say whoami, she does get to choose whether to authenticate as bob or tom :

 ==== AUTHENTICATION FOR org.freedesktop.policykit.exec ===
Authentication is needed to run `/usr/bin/whoami` as the super user
Multiple identities can be used for authentication:
 1. bob
 2. tom
Choose identity to authenticate as (1-2):
--UNQUOTE--