Proposal: allow to use i18n.getMessage in a serviceWorker

[carlosjeurissen]

With mv3, i18n.getMessage and i18n.getUILanguage are not a function in the service_worker background script. This is troublesome as this is needed to set the label of action buttons or the entries of context menus.

One of the reasons this might not be available is the sync nature of this method. Potentially we can resolve this by either offer an promise-based initialization function for this after which i18n.getMessage is available. Or make an async version of i18n.getMessage. Using fetch calls to the _locales files is not a viable alternative as this wouldn't allow the extension developer to rely on the native browser fallback system (es_419 would fall back to es). This would also be an issue since i18n.getUILanguage is unavailable and one has to rely either on navigator.language(s) or i18n.getAcceptLanguages which both would not give the language of the browser.

See also:

• Use cases that are not well served by service workers #72 (comment)
• Chromium extensions group report
• Chromium bug report 1175053
• Chromium bug report 1159438
• Chromium bug report 1268098

[ghostwords]

This might have gotten fixed in Chrome: https://bugs.chromium.org/p/chromium/issues/detail?id=1159438#c24

[carlosjeurissen]

This might have gotten fixed in Chrome: https://bugs.chromium.org/p/chromium/issues/detail?id=1159438#c24

Thanks for pointing that out! It actually hasn't been fixed. i18n.getUILanguage is now supported, yet i18n.getMessage is still unavailable.

[carlosjeurissen]

Opened a new issue for it specifically for i18n.getMessage:
https://bugs.chromium.org/p/chromium/issues/detail?id=1268098

[dotproto]

Thanks for opening that issue, @carlosjeurissen. To my knowledge Chrome intends to support i18n.getMessage() in Manifest V3, but in order to do so we need to tweak this method to be asynchronous due to the inherently async nature of service workers.

[carlosjeurissen]

@dotproto Thanks for the update. Are there any proposals on how to do that? Potentially we can do something like i18n.initialise('$ieft_tag') which returns a promise which resolves when i18n.getMessage works. This would also cover https://crbug.com/660704

[maximtop]

On Chrome 103.0.5060.134 seems to be working already.

[xeenon]

I think we can close this. It was simply a bug in Chrome, and Safari has supported this in v3 since supporting v3.

[carlosjeurissen]

@xeenon Thanks for the added labels and closing the issue. Seems serviceWorkers are not yet supported in Firefox, however, this API will probably work just fine once they do.