Shortly: How can I enable privileged code by default (in Firefox 22, or newer)? Since it is only for local purposes on several computers in laboratory - I can edit any Firefox files. In case of questions "why?" or answers unrelated to Firefox: I am using some privileged code from normal website (opened locally from file on local computers only) and since netscape.security.PrivilegeManager.enablePrivilege vanished from Firefox I cannot run privileged code from normal content after versions 17. I need to enable some features like drawWindow and file access from normal page by default. I use scripts that allow user (in laboratory on lab computers) to enter normal websites, collect data about user activities, log what was clicked, than take screenshots of webpage after action, than save pictures to hard drive. Users are essentially testing given webpages - UX tests and Firefox greatly help(ed?) with such tests. But I really do not have such possibilities like rewrite everything to plugins or take screenshots manually or from something like Greasemonkey. Other options like camera or software to record screen are also not possible. Thanks in advance.