+While the daemon is stopped or disconnected, the WhatsApp servers keep
+the messages for the linked device and send them at the next connection.
+They keep them only for a limited time, so a long stop can lose
+messages. These messages form batches by their original times, as live
+messages do. The daemon waits for the end of this catch-up, or one
+minute at the most, and then gives all its batches to the agent in one
+turn, not one turn for each chat. The batches of ``whatsapp/state.json``
+at the start wait for the first catch-up in the same way.
+