Did you install the xfce4 desktop env? If not, install it.

Yes:

kali-desktop-xfce is already the newest version (2019.4.21)

Unless I'm missing something?

Yes:

xfce4 is already the newest version (4.14)
kali-desktop-xfce is already the newest version (2019.4.21)

Unless I'm missing something?

Is this file exist:
/usr/lib/x86_64-linux-gnu/xfce4/notifyd/xfce4-notifyd

It should be running.

No it was not running. When I run it, and then run kali-undercover, xfce4-notifyd terminates

Try to remove and install the xfce4-notifyd
If it still not working, I need more information from your side, like the error logs.

used apt to remove and reinstall, didn't work.

Which logs do you need?

Chances are you installed XFCE but you are still running Gnome. Undercover only will work when you are running XFCE. Please review https://www.kali.org/docs/general-use/xfce-faq/ on how to switch over.

Thank you for your interest in Kali but please use forums or IRC for further questions. This is a bug tracker, not a support forum.

I'm curious why you consider this support? I can't get it to work no matter what people here have suggested so far, and I doubt I will be the only one as this is a new feature. Are you 100% sure that this isn't a bug? If so, go ahead and close again.

As we mentioned, this is happening to you because you are not running XFCE. You are still running the Gnome DE. As we said, you have instructions at https://www.kali.org/docs/general-use/xfce-faq/ telling you how to switch.

To make it easy for you - If you see the doc on the left hand side of the screen you are still in Gnome and have not switched to XFCE correctly. If you show that you are in fact logged into XFCE and undercover is not working, then yes that would be a bug. If thats the case, send us a screen shot of the issue. However, based on everything you have said in this report, you are still logged into gnome and this is just simply user error.

Fair enough, but even after removing gnome, choosing xfce on the login page before logging in, and then upon logging in, still a doc. Ugh... go ahead and close. Your link here seems to make it sound like it's a point and click solution after upgrading, which it definitely is not for myself and a coworker.

Thanks

Please send a screenshot of what is going in in that case. We would need more information than what is provided.

I don't mean to sound rude, Kali is great, it's just frustrating since at times it feels like you need to be a Linux sysadmin to get basic functionality.

Apologies...

After running "update-alternatives --config x-session-manager", choosing the xfce option, and rebooting, all is well.

Thanks for your patience, I'm certainly not Linux expert clearly!

Thanks, closing.