How to prevent a program from accessing the Internet?

Question

firewall

Windows 10-1909. I wanted to prevent firefox from accessing the Internet (in general, for curiosity, how it works). I did it through PowerShell in the firewall:

New-NetFirewallRule -DisplayName "Block Firefox" -Direction Outbound -Program "C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -Action block

The task for blocking was added perfectly, but it does not work! FF still loads websites just fine.

In the firewall, I added a blocking rule for incoming connections to FF - with the same result.

I tried to block other programs - also with zero results.

And only if you check "All programs that meet the conditions", then the firewall blocks all access to the Internet (see figure).

Question: how can I block the Internet for a specific program, even for the same firefox?

Answer 1

Look here.