The one exception to the "no server" principle
Community lists let you fetch shared filter lists from an address you choose yourself. Off by default, never automatic, always triggered by hand.
What Noise Guard actually does
If the feature is actively enabled and a list address entered, Noise Guard can fetch it on request. New suggestions (e.g. additional filter terms) are shown but never adopted automatically, you review and confirm each entry individually or in bulk.
This address is the only network connection Noise Guard makes anywhere in the entire product. Without this feature, Noise Guard never sends anything to any server.
Why any exception to local-first at all
Some filter rules (like new ad domains or current manipulation patterns) change faster than a fixed, bundled list can keep up with. Shared lists solve this without Noise Guard itself becoming a centrally controlled cloud detection system. Control stays entirely with you: you choose the source, you confirm every change.
What actually happens when fetching
Clicking "Check now" triggers exactly one network request to the address you entered, with a 10-second timeout. If the server doesn't respond in time or returns an error status, Noise Guard stops and reports that honestly instead of silently retrying in the background.
The response must be a JSON file and can be at most 2 MB, anything else is discarded before it's even processed. Every single suggestion from the list gets its own signature, so the same rule isn't suggested repeatedly no matter how often you fetch the list. At most 300 not-yet-decided suggestions are kept at once, older ones drop off otherwise.
None of this is automatically applied to your active filter rules. Every suggestion sits individually pending review until you confirm or reject it.