Affected versions

• Fx 87.0
  Fx 88.0b9
  Fx 89.0a1 (BuildID: 20210416093642)

Affected platforms

• Windows 10 x64

Steps to reproduce

1. Use the .exe firefox installer.
2. Set a custom installation path to a folder on the desktop.
3. Let Firefox install.
4. Open Windows Firewall.
5. Create a new rule to block the Firefox .exe (the one installed on the desktop)
   5.1. In Windows Defender with Advanced settings.
   5.2. Select Outbound rules.
   5.3 Select new rule.
   5.4 Select program.
   5.5 Select the path to the program installed on the desktop.
   5.6. Select Block the Connection.
   5.7. Have Domain, Private, Public ticked on.
   5.8. Give it a name.

Expected result

• Firefox is blocked by the Firewall.

Actual result

• Firefox is not blocked and you can roam the internet freely.

Regression range

• Will return with a regression range if this is not a windows issue.

Additional notes

• Blocking the same exe but installed in the default path works as intended.
  There are no other rules allowing Firefox.

I was able to reproduce the issue on Win10 x64 using builds 55.0a1 (20170401030204), 61.0a1, 68.0a1, 76.0a1 and latest 95.0a1 (20211101084651).