Pocket caused a stir because it broke Mozilla's commitments to privacy, interoperability, and FOSS. They removed an open source end to end encrypted reading list feature in development and replaced it with a proprietary 3rd party data miner. They promote it with the lie "privacy is paramount" still.[1] And they responded to correct guesses Pocket paid Mozilla by denying Pocket paid them for the integration until it came out Pocket paid them for referrals. Trying harder to hide Pocket's nature would have amplified the loss of trust.

[1] https://www.mozilla.org/en-US/firefox/pocket/