I just opened the Whatsapp web app (never used it before), and then immediately set Airplane Mode on my phone as soon as it scanned the QR code. WhatsApp manag

I just opened the Whatsapp web app (never used it before), and then immediately set Airplane Mode on my phone as soon as it scanned the QR code. WhatsApp managed to load all my conversations (I don't have many) and the most recent message, for display in the list-view. But each conversation only has the most recently sent message. After a while I got a "Phone Not Connected" message. Seems like it really is only stored on your phone.