''locking as a duplicate of https://support.mozilla.org/en-US/questions/1014119'' I recently upgraded my firefox to the latest version i.e 31.0. But after that things messed up. I now no longer can use the firebug extension i.e I am not able to see any icon for firebug anywhere and no option in the context menu as well where there used to be an option for firebug earlier. I even tried updating the extension to the latest version. But all in vain. Upon seeing the list of addons, I am able to see firebug as installed addon. But I don't see any option anywhere else in the browser to use it. Seems like downgrading is my only resort now. Can anybody help me out on this. I am badly stuck with my work because of this. Thanks in advance.