My firefox has also been upgraded to 43.0.1 and as a result Zotero was disabled. I installed the latest version of Zotero (4.0.28.10) and the associated plug-in for word (3.5.4) and it now works, however word now has two Zotero plug-ins on the ribbon: the new plug-in called 'Zotero' on the ribbon, as well as my old plug-in called 'Add-ins'. Both work. How do I delete the old plug-in? I'm concerned the presence of two could corrupt my files. Thank you:)