Facebook’s AI-driven M assistant chatbot has safely made it across the Atlantic and is now helping Messenger users in the UK. The chatbot will butt into your conversations if it feels it can be of assistance. For example, when discussing making plans it could find you nearby places, create a poll about where to go, and find time in participants’ diaries. When you arrive you could follow up with a question like “Where are you?” and the chatbot will prompt the other person to send...