To disable it in about:config
browser.search.serpEventTelemetry.enabled = false
browser.search.serpEventTelemetryCategorization.enabled = false
To disable it in about:config
browser.search.serpEventTelemetry.enabled = false
browser.search.serpEventTelemetryCategorization.enabled = false
Syncthing is one of the best examples of telemetry done well. On first startup, they ask if you agree to enable telemetry, they show the data that will be send and inform users that the collected data can be viewed at https://data.syncthing.net/