Zotero icon disappeared

This is pretty weird: I launched Firefox this morning and all of a sudden the Zotero icon is gone from my browser. My library is still there, I can still access it using the Tools menu and the keyboard shortcut, but the icon is just gone... I tried changing the Zotero prefs around and restarting Firefox and my computer, to no avail. Does anybody know how to fix this?

Thank you!
This discussion has been closed.