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Firefox constantly sending data 3KByte/S to Cloudflare servers

Firefox Privacy and security
jbr replied
GT2026-XYZ
GT2026-XYZ

I have recently discovered that Firefox is constantly sending data at around 3KBytes/S to a variety of Cloudflare servers.

What is the data that is being sent and why is this happening?

This has started to occur in one of the last updates to Firefox.

Currently running 151.0.4 (64-bit) on Windows

Does this constitute a privacy violation, what is the data that is being sent?

I have recently discovered that Firefox is constantly sending data at around 3KBytes/S to a variety of Cloudflare servers. What is the data that is being sent and why is this happening? This has started to occur in one of the last updates to Firefox. Currently running 151.0.4 (64-bit) on Windows Does this constitute a privacy violation, what is the data that is being sent?

All Replies (1)

jbr
jbr
  • Top 10 Contributor

And you don't have Cloudflare set for Firefox DNS over HTTPS as the provider? (It should not be requesting things constantly even when idle but there's enough internal service endpoints to hit even in background to generate DNS traffic however I'd expect for the same hosts this to be reasonably cached to start with.)

If you create a new clean profile without addons and no tabs/sessions to restore, do you still see it?

Generally most of Mozilla traffic terminates at Fastly POPs, incl. OHTTP and IP protection features.

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