This was a suggestion from https://bugzilla.mozilla.org/show_bug.cgi?id=1139165#c6 : > Again, IMO, for the future (if not already in works), this should be > separated from Firefox in a way that it does not require an update of FF > software and something like a plugin/extension update takes care of it > instead. There are both pros and cons to doing this, but I figured I'd file a separate bug for it, at least.

> There are both pros and cons to doing this, but I figured I'd file a > separate bug for it, at least. I would say this is a good idea. It will help us deliver better Readability.js algorithm to end-users more quickly. But I don't know what are the cons? After investigating, we might need to build the system add-on with classical add-on technology not WebExtensions because of the below reasons * WebExtensions cannot reuse some jsm modules that are used in current reader module module, e.g. [`LanguageDetector.jsm`][reader-dependency-1]. * The reader mode module depends on the Pocket system add-on's [services messages (`Reader:AddButton` and `Reader:RemoveButton`)][reader-dependency-2] for [reader-dependency-2]adding/removing the pocket button on reader mode view. * The Pocket system add-on is using [`ReaderMode.jsm`][pocket-dependency-1] that is one of reader mode modules. But I think we should remove it after we finish the system add-on work. * Fennec is using some current reader mode modules, e.g. [AboutReader.jsm][fennec-dependency-1] and [ReaderMode.jsm][fennec-dependency-2]. At the same time, we also need to take a look at Fennec. But I'm not familiar with Fennec code base, I'm not sure what issue will we have if we make reader mode as a system add-on on Fennec? I know that Fennec can install add-ons (so system add-on also works on Fennec?) and Fennec sents [`Reader:ToggleReaderMode` service message][fennec-dependency-3] to trigger reader mode. So if Fennec support system add-on function does that mean we could build a read mode system add-on for Firefox Desktop and Fennec at the same time? What do you think, Gijs? [pocket-dependency-1]: http://searchfox.org/mozilla-central/search?q=ReaderMode&case=true&path=browser%2Fextensions%2Fpocket [reader-dependency-1]: http://searchfox.org/mozilla-central/search?q=LanguageDetector&case=true&path=toolkit%2Fcomponents%2Freader [reader-dependency-2]: http://searchfox.org/mozilla-central/source/toolkit/components/reader/AboutReader.jsm#204-222 [fennec-dependency-1]: http://searchfox.org/mozilla-central/source/mobile/android/chrome/content/content.js#12 [fennec-dependency-2]: http://searchfox.org/mozilla-central/source/mobile/android/chrome/content/content.js#13 [fennec-dependency-3]: http://searchfox.org/mozilla-central/source/mobile/android/chrome/content/content.js#37-47 [fennec-dependency-3]: http://searchfox.org/mozilla-central/source/mobile/android/chrome/content/content.js#37-47

Clearing this needinfo because Evan and I are talking over email. For now, because of mobile and because of time constraints, I don't think we'll be investing in making reader mode a system add-on. We can re-evaluate in the future if the situation changes significantly.

Agree, let's re-evaluate in the future.