The Add-on Localization Campaign is happening: Join us!

Hello Mozillians,

Note: This campaign is finished, we have published a blog post here and a thank you note.

Starting today and until July 2nd, join forces with your fellow Mozillians and help top Firefox Add-Ons by localizing them into the top 10 languages.

Are you ready? Find your language below, log-in and help by suggesting localizations or reviewing existing ones by upvoting them. It’s very easy, check the style guides for your language and the instructions below on how to use the tool if you need help.

Once you click one of the links you will be asked to log-in, use any existing service or create an account with you email.

In the localize mode you can navigate all pending strings in the left column, suggest a localization and click save in the middle column.

In the review mode you can see suggestions that other people have done and upvote (+) or downvote (-) them, this is important to ensure quality.

That’s all! Trusted Mozilla localizers will be checking all the review votes at the end of the campaign to do the final approval of the strings.

Do you want to talk about the campaign in social media? Just don’t forget to use the #addonsl10n hashtag. Also, feel free to organize one day to gather offline or online (Vidyo, Telegram, IRC, Hangouts…) with your community to localize and review together your language.

If you have any questions, don’t hesitate to ask here.

Let’s help million of users and show the world what our communities can accomplish.

See you all (virtually) there!


  • June 18 to July 2nd - Localization and review phase.
  • July 2nd: Localization finished, we start to upload AMO descriptions, QA phase starts.
  • July 5th: We deliver final strings to authors.
  • July 11th: Authors publish new version with localizations, we start the marketing promotion + blog post, we start measuring.
  • July 28th: Initial report with metrics.


Why this campaign is just limited to 10 locales?

In order to run a experimental campaign with the resources we had in terms of time and people we decided to limit the number of locales to the top 10 with more Firefox Desktop users.

Why the localization is not done in Mozilla’s pontoon?

At the time of planning the campaign, Pontoon was not ready to handle add-on localization files and a permission system to accommodate to the campaign needs.

Why we are using this tool?

We had good experiences in the past with this tool (for Common Voice campaign) and the user interface was the most similar to our pontoon.

Are we expanding our support to Add-ons localizations in the future?

If we are successful with this campaign (more people install add-ons in these locales) we will be able to make a case to increase the support to this kind of work.

Is the localization workflow different?

Slightly different, we want anyone to be involved in the localization suggestions and review, and we asked existing core localizers to be involved only in the final approval phase, so we provide space to new people or people who has been more casual in the past.

Who will approve the localizations?

Existing core localizers for the target locales will be in charge of doing the final “green light” for the localization.

Which add-ons are part of this campaign and why?

Please check the full explanation below.

Why this effort is important for Firefox?

A recent study showed us that users who discover add-ons show ~10% increase in engagement with the browser. With this campaign we want to demonstrate that by having these add-ons in people’s language they install them more. This would link to direct value to Firefox engagement numbers, which is key for our browser to stay relevant in the market.

Open Innovation


Please, feel free to add any questions here, I will update the FAQ in accordance.

For Italians that arrive to that page, Mozilla Italia community is starting to work with a specific thread in our forum ->
We will probably use also Telegram to coordinate between us, if you want join us check the forum!

1 Like

As a decade long user of babelzilla, it is not clear to me what projects / Add-ons the translations presented are for. Context matters. I tried the filter facility but that doesn’t appear to list any context either. It makes more sense to target specific add-ons and be able to download (half) translated versions of the Add-on to do test runs. In Babelzillla you get to choose downloading locales with untranslated strings skipped or replaced, making it easy to create test builds of the ADd-ons to try them out. Maybe I am missing something and the translations is only for the AMO web pages or Firefox core ?
I am particularly interested in helping with Mail Add-ons, is there a restriction to Web Extensions only, or can we still help with XUL Add-ons?

Sorry, let me provide context. We selected 11 add-ons based on the following criteria:

  • Popular (>0.5% users) in at least 3 of the target locales.
  • Using an open source license.
  • The author replied and was willing to incorporate the strings for the campaign dates.

We also included a few add-ons which were extremely popular in this 10 locales plus a small editorial selection from the Addons Team. We had to exclude some add-ons which code was not ready for localization.

The final list is:

  • AdBlock for Firefox
  • 1-Click YouTube Video Download
  • Greasemonkey
  • Download Flash and Video
  • NoScript Security Suite
  • signTextJS plus
  • To Google Translate
  • Pinterest Save Button
  • New tab override
  • HTTPS Everywhere
  • Stylish

Note that we will localizing both the add-ons and their descriptions/summaries on site.

Once all the strings are approved, we will be generating and distributing testing versions of the add-ons to localizers so they can check everything is fine.

How are translations transferred to AMO? Is that an automated or a manual process?

For the add-ons strings authors will upload new versions, for the AMO descriptions and summaries @jorgev will run a script to upload them all at once.


I do what is necessary for French



Thanks @hellosct1 Remember to share with your fellow French-speaker mozillians, I’m sure we can find new people to get involved with Mozilla thanks to this campaign! :smiley:

1 Like

Campaign day 2 - Stats

Some numbers of the campaign’s day 2

  • Number of participants: 35
  • Words translated: 9701
  • Locales with no activity yet: Dutch, Japanese



Remember to also use the “review” link for your locale and vote for good suggestions, this will allow speed up the final string approval.


Campaign day 4 - Stats

Some numbers of the campaign’s day 4

  • Number of participants: 50
  • Words translated: 19517
  • Locales with low activity: Japanese, Dutch, Polish, Russian


Congratulations to Chinese, which already have all suggestions covered, now they are in the review phase, voting suggestions to help core localizers approve the final strings.


Keep the great work! :muscle::fox_face:

I see also people adding comments on the strings on Crowdin but no reply to them so they work on the other strings and this pending remain incomplete.

Campaign day 7 - Stats

Some numbers of the campaign’s day 7

  • Number of participants: 74
  • Words translated: 29388
  • Locales with low activity: Japanese, Polish, Russian


Chinese just needs to validate all the complete suggestions. Spanish, Dutch and Italian are close to complete all suggestions, German and French follow close.

Russian, Portuguese, Polish and Japanese need a big push, we are just one week away of the end of the campaign.


Keep the great work! :muscle::fox_face:

PS: Great job for italian during the weekend btw! :smiley:

Congratulations to Spanish and Portuguese! They are now ready for review.

But remember, we still need to keep voting strings in the review mode to help approvers with the final check, this is as important as suggesting strings :smiley:

PS: Dutch is close to complete all suggestions and Japanese, Polish and Russian still need more people involved!

Campaign day 9 - Stats

Some numbers of the campaign’s day 9

  • Number of participants: 84
  • Words translated: 44045
  • Locales with low activity: Japanese, Polish, Russian


Spanish, Dutch, Portuguese and Italian did an amazing work in the past days, completing their suggestions. Russian, Portuguese, Polish and Japanese still need a big push.

Important: Remember that having all suggestions is not enough to validate your language, please keep voting for good suggestions in the review mode, core localizers rely on these votes in order to speed up the process and approve the final strings (green bar in the graph below).


Keep the great work, and remember to vote strings! :muscle::fox_face:

Campaign day 11 - Stats (3 days left!)

Some numbers of the campaign’s day 11, just 3 days away until the end of the campaign

  • Number of participants: 91
  • Words translated: 58675
  • Locales with low activity: Japanese, Polish, Russian


Chinese, Dutch, Italian, Portuguese and Spanish are approving the final strings, excellent work from these communities.

French and German still need a final push if they want to get in time for the end of the campaign, if you know the language please chime in and help today!

Unfortunately Russian, Japanese and Polish haven’t got a lot of contributions and are still mid-way with the suggestions. If you are in these locales, please organize a day during this weekend to suggest and vote strings.


As I previously commented, we are 3 days away from the final date, July 2nd, where we will start generating the Add-ons for testing only for the locales that have all strings approved.

Thanks to everyone who has been involved so dar!

PS: Special shout out to @philipp (German) and Tonnes (Dutch), @sara_t (Italian), Breaking_Pitt (Spanish) and @xcffl (Chinese) who made a huge push in their languages progress during the last 2 days :muscle::fox_face:

I’ve updated the first post with the upcoming milestones for this project:

  • July 2nd: Localization finished, we start to upload AMO descriptions, QA phase starts.
  • July 5th: We deliver final strings to authors.
  • July 11th: Authors publish new version with localizations, we start the marketing promotion + blog post, we start measuring.
  • July 28th: Initial report with metrics.

Today is the last day, is there still translation to be done?



For French I see that just a few approvals are needed, almost there. @theo and @benoit.leseul were coordinating there :smiley: