Mozilla’s New Rule: Firefox Extensions Must Come Clean on Data Collection!
Starting November 2025, Firefox extension developers must disclose if their add-ons collect or share user data. This info goes in the manifest.json file, ensuring transparency. Extensions with no data collection must also declare this. Non-compliance? Expect a “You Shall Not Pass!” block from Mozilla’s add-on repository.

Hot Take:
Hold onto your hats, Firefox fans! Mozilla is kicking the door down on shady extension practices, declaring war on sneaky data grabs with a transparency policy that’s about as subtle as a marching band at a library. Developers, brace yourselves: it’s time to come clean or take a hike. Your manifest.json is about to become the confessional booth of the digital age!
Key Points:
- Starting November 3, 2025, Firefox extension developers must disclose data practices in the manifest.json file.
- Disclosure includes whether extensions collect or share personally identifiable data.
- Developers must specify data collection practices even if no data is collected.
- New requirements apply to new extensions, with existing add-ons needing updates by early 2026.
- Non-compliance results in blocked submissions on Mozilla’s add-on repository.
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