I am unable to run Firefox 47 with Xvfb on Ubuntu 14.04.4 LTS 64 bit Codename Trusty. I have installed this VM on Windows 7 host with vagrant and Virtualbox as provider. Virtualbox Version: v5.0.20 r106931. Please help. Command: firefox --display=:10 http://www.google.com hangs for a while and fails with following error messages: 1465845198876 addons.update-checker WARN Update manifest for e10srollout@mozilla.org did not contain an updates property 1465845199022 addons.update-checker WARN Update manifest for firefox@getpocket.com did not contain an updates property 1465845199030 addons.update-checker WARN Update manifest for ubufox@ubuntu.com did not contain an updates property 1465845199038 addons.update-checker WARN Update manifest for {972ce4c6-7e08-4474-a285-3208198ce6fd} did not contain an updates property 1465845200145 addons.xpi ERROR Attempted to load bootstrap scope from missing directory /root/.mozilla/firefox/zzy7qmv1.default/extensions/firefox-hotfix@mozilla.org.xpi 1465845200145 addons.xpi WARN Add-on firefox-hotfix@mozilla.org is missing bootstrap method shutdown 1465845200149 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/zzy7qmv1.default/extensions/firefox-hotfix@mozilla.org.xpi!/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