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Add-ons

Release notes

Add-ons using the techniques described in this document are considered a legacy technology in Firefox. Don't use these techniques to develop new add-ons. Use WebExtensions instead. If you maintain an add-on which uses the techniques described here, consider migrating it to use WebExtensions.

Starting from Firefox 53, no new legacy add-ons will be accepted on addons.mozilla.org (AMO) for desktop Firefox and Firefox for Android.

Starting from Firefox 57, only extensions developed using WebExtensions APIs will be supported on Desktop Firefox and Firefox for Android.

Even before Firefox 57, changes coming up in the Firefox platform will break many legacy extensions. These changes include multiprocess Firefox (e10s), sandboxing, and multiple content processes. Legacy extensions that are affected by these changes should migrate to use WebExtensions APIs if they can. See the "Compatibility Milestones" document for more information.

A wiki page containing resources, migration paths, office hours, and more, is available to help developers transition to the new technologies.

Firefox 35

Highlights

Details

GitHub commits made between Firefox 34 and Firefox 35. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 34 and Firefox 35. This will not include any uplifts made after this release entered Aurora.

Firefox 34

Highlights

Details

GitHub commits made between Firefox 33 and Firefox 34. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 33 and Firefox 34. This will not include any uplifts made after this release entered Aurora.

Firefox 33

Highlights

Details

GitHub commits made between Firefox 32 and Firefox 33. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 32 and Firefox 33. This will not include any uplifts made after this release entered Aurora.

Firefox 32

Highlights

Details

GitHub commits made between Firefox 31 and Firefox 32. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 31 and Firefox 32. This will not include any uplifts made after this release entered Aurora.

Firefox 31

Highlights

Details

GitHub commits made between Firefox 30 and Firefox 31. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 30 and Firefox 31. This will not include any uplifts made after this release entered Aurora.

Firefox 30

Highlights

Details

GitHub commits made between Firefox 29 and Firefox 30. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 29 and Firefox 30. This will not include any uplifts made after this release entered Aurora.

Firefox 29

Highlights

Details

GitHub commits made between Firefox 28 and Firefox 29. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 28 and Firefox 29. This will not include any uplifts made after this release entered Aurora.

Firefox 28

Highlights

Details

GitHub commits made between Firefox 27 and Firefox 28. This will not include any uplifts made after this release entered Aurora.

Bugs fixed between Firefox 27 and Firefox 28. This will not include any uplifts made after this release entered Aurora.

 

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 Contributors to this page: wbamberg
 Last updated by: wbamberg,