I have spent hours and hours trying to fix this. Facebook pages do not show their TABS under the cover photo. I have attached a screenshot of an example at https://www.facebook.com/pages/Betfair-Trading/596591180403116 Below the cover photo, if I use ANY browser except Firefox, (Safari for instance), it shows tabs "Timeline", "Photos" etc etc But not in Firefox, it's blank. I researched for hours, and this led me firstly believe it is my Adblock addon. So I disabled that. No joy. I then ran safe mode, to rule out all addons, same. I then cleared cache and all data. Same I then found a few threads talking about "Mixed Content". All threads and instructions written for PC users, I AM ON A MAC. I even went as far as following some coder's instructions about doing "about:config" in FF, then searched "Mixed" and then changing some values in there to try to force it to stop blocking mixed content. No joy either. I am now convinced it is nothing to do with Mixed Content. Unfortunately after many many years of happy use of firefox, and after recommending it to many friends and clients, I can no longer use it myself. Fancy that, a browser which can't display webpages properly from one of the few most popular sites on the internet! Any ideas before I dump it and go back to Safari after all these years?! P.S. After trying for 20 minutes, your post a question page doesn't seem to want to upload a photo. So I can't upload my screenshots, but will keep them in case this changes in the future. Basically the area where the tabs should be under cover photo is blank white space. In safari or chrome its got tab buttons to select tabs within the page.