In the readme file there exits an hint to the Firefox OS Marketplace. but it was closed on March 30th of this year.
Yes, the legacy of the Firefox OS lives on via KaiOS, I think that the Firefox OS version should be repackaged for KaiOS, since it is very important for emerging markets (https://react-etc.net/entry/kaios-2nd-most-popular-mobile-os-after-android-ios-drop). The UI would have to be tweaked, but most of the packaging work for Firefox OS still applies. The hardest part would be getting it into KaiStore (https://developer.kaiostech.com/others)
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Yes, the legacy of the Firefox OS lives on via KaiOS, I think that the Firefox OS version should be repackaged for KaiOS, since it is very important for emerging markets (https://react-etc.net/entry/kaios-2nd-most-popular-mobile-os-after-android-ios-drop). The UI would have to be tweaked, but most of the packaging work for Firefox OS still applies. The hardest part would be getting it into KaiStore (https://developer.kaiostech.com/others)