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README.md

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+Important Information
+=================
+From Firefox 57 onwards, WebExtensions will be the only supported extension type, and Firefox will not load other types. Which mean that the actual version of UNP won't work anymore.
+UNP rely on io/file api which doesn't exist in WebExtension API (https://bugzilla.mozilla.org/show_bug.cgi?id=1246236). This means I'll have to create an external app in addition to simply porting UNP to WebExtension.
+To be honest, I kind of lost interest in developping browser extension (and I'm not using UNP since years).
+But I'll probably to the work someday if enough people find this extension usefull (and are OK with running an external program in addition to Firefox or Chrome). And, of course, patch are always welcome :)
+
 [Untamed Now Playing](https://github.com/Wylk/Untamed-Now-Playing-Next)
 =================