Manifest v3 Opera

[vjik7]

vjik7 @gmiazga last edited by

@gmiazga Any news?

[gmiazga]

gmiazga Opera last edited by

It took way longer than expected but it's finally here. Changes have been deployed on production and it should be possible to upload extensions using manifest v3.

[carlosjeurissen]

carlosjeurissen @gmiazga last edited by

@gmiazga Thanks for the MV3 timeline!

Is it already clear how Opera will handle browser-specific choices and features?

• How will the sidebar API change in MV3? (See https://github.com/w3c/webextensions/issues/128)

Mozilla Firefox decided to handle MV3 a bit different than Chrome to help developers and users:

• Will the webRequest still be available in MV3 (Unlike in Google Chrome)
• Will Opera keep supporting non-persistent background scripts?

(When) does opera want to stop supporting MV2 extensions on the store and in the browser? Due to all the issues with MV3, can we as developers ask for extended support of MV2 on the Opera Store? Or allow publishing both MV2 and MV3 at the same time for best backward compatibility?

[alitoolsio]

alitoolsio last edited by

@gmiazga when is the full transition to Manifest V3 planned, and when will it be prohibited to load the extension with Manifest V2?

Or is there no certainty yet about when exactly this will happen, and it is safe to continue loading the extension with Manifest V2?

[Halterka]

Halterka @alitoolsio last edited by

@alitoolsio I noticed that few developers like SIMKL's Netflix Enhancer have already started updating their browser extension to Manifest V3.

I still kinda use those old browser extension that run on Manifest v2 (which were not updated for ages) but still useful to me - I wonder, what will happen to those apps.

[carlosjeurissen]

carlosjeurissen last edited by

People are reporting mv3 warnings in the extensions panel.

https://forums.opera.com/topic/36230/app-launcher-customizer-for-google/32

Why is this appearing before Opera gave any statement on their mv3 schedule? What is the timeline?

[leocg]

leocg Moderator Volunteer @carlosjeurissen last edited by

@carlosjeurissen Probably is Chromium doing it.

[carlosjeurissen]

carlosjeurissen @leocg last edited by

@leocg Yes, still would be nice if Opera would hide these warnings for the time being until they have an mv3 schedule.

[pilis00]

pilis00 last edited by

Any updates on MV2 removal?

[erdinc53]

erdinc53 @pilis00 last edited by

@pilis00 Nope, MV2 will continue to live in Opera.

[pilis00]

pilis00 last edited by

An update from an Opera developer would be a lot better to be heard.

[erdinc53]

erdinc53 @pilis00 last edited by

@pilis00 Yes, In Chromium 139, they will make a statement when support is officially cut off.

[pilis00]

pilis00 last edited by

Who told you that?

[erdinc53]

erdinc53 @pilis00 last edited by

@pilis00 nobody. Just a guess.

[wezelkrozum]

wezelkrozum last edited by

I did receive the following message when I updated my manifest v2 extension early this month:

Message from moderator:
Hello,

Manifest V2 is deprecated and MV2 extensions will stop functioning soon.

Ambient light for YouTube v2.38.13 on Opera Developer: Published.
Ambient light for YouTube v2.38.13 on Opera Next: Published.

Moderator; Jun 10, 2025 7:29:31 AM UTC

I asked for a timeline but didn't get an answer. So I updated it to v3 just to be safe.

[erdinc53]

erdinc53 @wezelkrozum last edited by

@wezelkrozum Mv2 add-ons currently available in the store will be protected. Especially uBlock Origin.

[wezelkrozum]

wezelkrozum last edited by wezelkrozum

I did receive a follow-up yesterday:

Hello,

I'll request to remove the post or at least correct it. This is informational mistake.

"Starting in June, the branch for Chrome 139 will begin, in which support for Manifest V2 extensions will be removed from Chrome. Unlike the previous changes to disable Manifest V2 extensions which gradually rolled out to users, this change will impact all users on Chrome 139 at once. As a result, Chrome 138 is the final version of Chrome to support Manifest V2 extensions"

We as Opera probably will sync an 139 intake in August/September 2025.

Sorry for the confusion.


Moderator; Jul 4, 2025 2:30:48 PM UTC

[erdinc53]

erdinc53 @wezelkrozum last edited by

@wezelkrozum What do we need to understand from this?