I have a problem with zotero for firefox today. I use zotero for a long but today, when I tried to add citation using Zotero, this does'nt work. The icon remains grey and not working. when I click on it I am informed that "zotero is offline", sometime "save to zotero (embedded metadata)" or "save to zotero (web Page with Snapshop)" or "save to zotero (web Page with Snapshop)" or zotero connector is currently unavailable