Since long time, we use firefox in our Document Management System to open files on the lan of our compagny with a script in javascript containing: window.open('file:///F:/asamplefile.odt','document','width=50,height=10'); with the configuration of firefox: lockPref("capability.policy.localfilelinks.checkloaduri.enabled", "allAccess"); lockPref("capability.policy.localfilelinks.sites", "http://mylanserver"); lockPref("capability.policy.policynames", "localfilelinks"); lockPref("capability.principal.codebase.p0.granted", "UniversalFileRead"); lockPref("capability.principal.codebase.p0.id", "http://mylanserver"); lockPref("capability.principal.codebase.p0.subjectName", ""); Since we upgraded to FF 60.0.1 and more, it doesn't work any more. the error is: Access to file 'file:///F:/asamplefile.odt' from script denied Is it possible with a new configuration in FF 63 ?