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Firefox might not meet your definition but with a few extensions (Containers, NoScript, uBlock origin) it's quite good at protecting your privacy.

The only thing is they integrate things like pocket and they're putting some other things in soon.

Pocket is part of Mozilla

And it still is not open-sourced, two years and five months after the acquisition: https://github.com/Pocket/extension-save-to-pocket/issues/75

For comparison, it took Red Hat less than two years to open source Ansible Tower.