Mozilla to Require Data-Collection Disclosure in All New Firefox Extensions

"Mozilla is introducing a new privacy framework for Firefox extensions that will require developers to disclose whether their add-ons collect or transmit user data..." reports the blog Linuxiac: The policy takes effect on November 3, 2025, and applies to all new Firefox extensions submitted to addons.mozilla.org. According to Mozilla's announcement, extension developers must now include a new key in their manifest.json files. This key specifies whether an extension gathers any personal data. Even extensions that collect nothing must explicitly state "none" in this field to confirm that no data is being collected or shared.

This information will be visible to users at multiple points: during the installation prompt, on the extension's listing page on addons.mozilla.org, and in the Permissions and Data section of Firefox's about:addons page. In practice, this means users will be able to see at a glance whether a new extension collects any data before they install it.

The Telemetry Wars

[geekmux]

I can kinda see the next move on the chess board here. Microsoft blocking Firefox installs. For “security” reasons of course.

Hope Mozilla understands their dependencies..

Re:

[evanh]

It's just extensions. M$ doesn't have any skin in this.

Teapot, Kettle

[RegistrationIsDumb83]

So they're going to do the same to themselves, right? All that telemetry they do themselves (plus the rights to user data Mozilla forces users to fork over) should be just as visible.

Re:

[Valgrus Thunderaxe]

Mozilla already discloses this.

Disclosure alone is not enough

[devslash0]

Someone's got to verify the extension. Otherwise, they can do what they want.

Re:

[PsychoSlashDot]

Someone's got to verify the extension. Otherwise, they can do what they want.

Really, there should be protected actions and when an extension asks to do them we should need to approve them.

"This extension is trying to modify the layout of the interface. Allow/Deny?"
"This extension is trying to make a connection to an outside server. Allow/Deny?"
"This extension is trying to access local files outside its temp files. Allow/Deny?"
"This extension is trying to modify the payload of the website you are visiting. Allow/Deny?" "This extension is trying to read the websites you visit

Re:

[JamesTRexx]

Likewise, I'd like Firefox to have those same requirements for their own browser.

Allow Google to snoop on your behaviour? Yes/No.

Re:

[markdavis]

>"Really, there should be protected actions and when an extension asks to do them we should need to approve them."

+1, I would like to see that

How can I check my extensions ?

[greytree]

Is there a convenient way to see what my current extensions are doing with my data ?