The issue with Instagram's script for showing images not working in Firefox 23 is discussed in this thread: [https://support.mozilla.org/en-US/questions/967651 Unable to view photos on Instagram properly]. These other issues could be related. Unless you have seen something new, this is due to a change if Firefox that Instagram needs to respond to by changing its script. I have not seen a working solution for end users on this forum. (There might be something on a support forum at Instagram, if they have one.) By the way, are you sure you want the Zoomex extension? A Google search turns up numerous pages on how to get rid of it because it inserts ads into pages. You might consider disabling it here: orange Firefox button (or Tools menu) > Add-ons > Extensions category