Firefox Stop Home Calls

During my last Network Monitoring Scans, i found out that MANY of „free“ Software calls home permanently

Here’s a public Article
Article:
https://support.mozilla.org/en-US/kb/how-stop-firefox-making-automatic-connections

.. if you want to be safe, block all OUTGOING Traffic by a Firewall or local DNS Server and use a Proxy with Auth Mechanism!