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I prefer PortsMonitor. It shows a little more than Netiquette.

There's an extension for other browsers but no Safari version.
PortsMonitor shows Safari connections.

Be aware that for Safari there can be confusion due to a) the use of iCloud Private Relay, and b) increasing use of UDP. For example, my Safari makes IPv6 UDP connections to Apple's iCloud Relay servers and not much else. Also related issues with full VPN products.
 
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