Why are Google Chrome extensions not compatible with Firefox?

Question

I see many HNers supporting Firefox and lament as it's usage lessens. I do too. Firefox is where I started web development back since the Firebug days.Today, I was thinking, that if Chrome extensions were compatible with Firefox, won't it's adoption be more?Couldn't Firefox put some kind of a compatibility layer for a majority, if not all, for the extensions?After all, they are primarily html, css and javascript, as far as I'm aware.I guess this is a very simplistic viewpoint as I'm not aware of all the complications that it involves.Maybe others more knowledgeable can shed some light?

input_sh · Accepted Answer

They absolutely are, there are only slight differences in APIs. It was the entire point of killing their old APIs and starting from scratch.
You can upload a .crx (Chrome's extension format) to https://www.extensiontest.com/ to check its compatibility with Firefox, most of the time it will be (or require very minimal changes).
The distribution is not compatible. Extension developers still have to upload and support their extension in a completely different store, which is where Firefox deviates from other Chromium-based browsers.

vtee44 · Answer

Aren&rsquo;t they easy to port? There&rsquo;s a list of the differences.https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/Web...For example, Chromium uses chrome namespace while Firefox uses browser NS. FF already has something called chrome that&rsquo;s older than chromium and probably conflicts with it. That&rsquo;s the key difference.Anyway, what are the worthwhile chrome addons that aren&rsquo;t on FF?