It seems that LuLu simply don't work

[Masroor69]

I installed the Lu Lu app as mentioned in the documentation, on Sequoia 15.0.1.
add the network extensions and allow it to have control of the network.

and add the Telegram app to Block List

However, it seems that Telegram is still connecting and is able to transmit the data to its servers.

[mpas97]

Yeah, Apple messed everything up with macOS Sequoia. See eg. #643 where we are already discussing this behaviour. But it's not this plugin's fault if Apple decides to make the firewall behave like it's disabled and make all security plugin useless...

[Masroor69]

Yeap, I found that, if you disable the system-level firewall you can leverage the LULU.

[JStrategic]

Interestingly enough, I downloaded little snitch mini to see if it is encountering the same issue and little snitch seems to be working with the apple firewall enabled as well, not sure on the difference in how that application is handling the network filtering but thought I'd mention it.

[Masroor69]

One of the options I tested then was Little Snitch and it's not working with a system-level firewall. But it seems they solved the problem in the latest release as you said