"Bug in French government’s WhatsApp replacement let anyone join Élysée chats" by Sean Gallagher https://arstechnica.com/information-technology/2019/04/french-governments-secure-chat-app-left-door-open-to-outsiders/
I wonder how many of these bugs were in Matrix itself rather than the French government's fork? Either way, it's good that it's getting put through the paces while it's in beta.