Lors de la création d'une clé par unetbootin

bonjour

lors d'une création de clé usb bootable par unetbootin, voici le long message que le terminal m'a adressé en fin de travail.
Je n'ai jamais eu de tel message ni d'une telle longueur... auparavant d'aucune distrib.
Je voudrais votre avis
merci
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MON INDICATIF:~$ unetbootin
MON INDICATIF:~$ 1467199901331 addons.update-checker WARN Update manifest for ***@*** did not contain an updates property 1467199901792 addons.update-checker WARN Update manifest for ***@*** did not contain an updates property 1467199902061 addons.update-checker WARN Update manifest for {972ce4c6-7e08-4474-a285-3208198ce6fd} did not contain an updates property 1467199902252 addons.update-checker WARN Update manifest for ***@*** did not contain an updates property 1467199904305 addons.xpi ERROR Attempted to load bootstrap scope from missing directory /root/.mozilla/firefox/py6ntv9a.default/extensions/***@*** 1467199904306 addons.xpi WARN Add-on ***@*** is missing bootstrap method shutdown 1467199904313 addons.manager WARN Exception calling callback: [Exception... "Component returned failure code: 0x80520006 (NS_ERROR_FILE_TARGET_DOES_NOT_EXIST) [nsIFile.isDirectory]" nsresult: "0x80520006 (NS_ERROR_FILE_TARGET_DOES_NOT_EXIST)" location: "JS frame :: resource://gre/modules/addons/XPIProvider.jsm :: getURIForResourceInFile :: line 1461" data: no] Stack trace: getURIForResourceInFile()@resource://gre/modules/addons/XPIProvider.jsm:1461 < this.XPIProvider.callBootstrapMethod()@resource://gre/modules/addons/XPIProvider.jsm:4686 < this.XPIProvider.uninstallAddon()@resource://gre/modules/addons/XPIProvider.jsm:4964 < AddonWrapper.prototype.uninstall()@resource://gre/modules/addons/XPIProvider.jsm:7198 < uninstallHotfix/<()@resource://gre/modules/addons/XPIProvider.jsm -> jar:file:///root/.mozilla/firefox/py6ntv9a.default/extensions/***@***!/bootstrap.js:78 < safeCall()@resource://gre/modules/AddonManager.jsm:179 < makeSafe/<()@resource://gre/modules/AddonManager.jsm:195 < Handler.prototype.process()@resource://gre/modules/Promise.jsm -> resource://gre/modules/Promise-backend.js:937 < this.PromiseWalker.walkerLoop()@resource://gre/modules/Promise.jsm -> resource://gre/modules/Promise-backend.js:816 < this.PromiseWalker.scheduleWalkerLoop/<()@resource://gre/modules/Promise.jsm -> resource://gre/modules/Promise-backend.js:750
1467202079724 addons.xpi WARN Add-on ***@*** is missing bootstrap method shutdown
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vous y comprenez quelque chose ?