Tor browser / Firefox telemetry data
https://seclists.org/fulldisclosure/2019/May/17
It seems this issue is still not fixed although it has been announced in May 2019. URLs containing "mozilla", "google" etc. (as described) can still be found in about:config
This is well known in Firefox and there are various user.js projects which eliminate background connections.
Although in the case of Tor Browser the IP address is anonymized this is still unacceptable, especially for a browser which claims to be focused on protecting privacy.
As a privacy focused user: I expect 0 (zero) background connections and no possibility to enable such (through preferences or through about:config).
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