Clarification about the deprecation timeline of classic add-ons

Kris Maglione kmaglione at
Mon Nov 28 18:43:10 UTC 2016

On Mon, Nov 28, 2016 at 10:11:42AM -0800, Andrew McKay wrote:
>On 28 November 2016 at 05:54, Wladimir Palant <trev at> wrote:
>> * Dropping support for non-WebExtensions lands behind a pref that is set to
>> false by default. This pref is set to true shortly before Firefox 57 is
>> released - on all channels simultaneously (meaning nightly, developer, beta,
>> release).
>> * Dropping supports for non-WebExtensions lands in Firefox 57 during its
>> nightly phase and takes effect immediately. This change then takes 18 weeks
>> to propagate to release.
>> Which one is it? This is important for our own scheduling given that Adblock
>> Plus has quite a few users on non-release Firefox versions. I really hope
>> that the plan is doing the former - otherwise it will effectively remove
>> several month from the timeline.
>I think we should aim for the former.
>I'm tempted to suggest we go one further and only restrict on Beta and
>Release. That would enable people still to tinker on Nightly or Dev
>Edition. On the other hand, this might not be a good idea because it
>will make it hard for us to finally remove things like the SDK from
>codebase in 2018 or beyond.

I agree. I think we should initially disable this in 47 beta and 
release, but leave it enabled in nightly, dev edition, and ESR for 
some intermediate period.

More information about the Dev-addons mailing list