I am porting a Chrome extension to FF using 'FF Addon SDK'. In the background script (main.js) file, I need to use the FF equivalent of... chrome.webNavigation.onBeforeNavigate.addListener() and chrome.tabs.onUpdated.addListener() I noticed that require("sdk/tabs").on only has open, close, finish, etc., but nothing to do with the navigation. I see a few solutions that use Page-Mod or show the solution for the old XUL way of developing FF Extensions. I am specifically looking for an FF Addon SDK (only) solution. Appreciate any inputs. EDIT: I was able to figure out an alternative for chrome.tabs.onUpdated.addListener() by using Progress Listener. Apparently, in FF it is called onLocationChange. Still looking for an alternative to chrome.webNavigation.onBeforeNavigate.addListener() removed wwe stream spam links