4	{ "payload": "p1\u4e16", "kind": "MSG_IN", "at_ms": 1, "future": true }
5	{ "payload": "p2\u4e16", "kind": "MSG_IN", "at_ms": 1, "future": true }
6	{ "payload": "p3\u4e16", "kind": "MSG_IN", "at_ms": 1, "future": true }
7	{ "payload": "p4\u4e16", "kind": "MSG_IN", "at_ms": 1, "future": true }
8	{"at_ms":1700000000000,"kind":"USER_INPUT","payload":"new"}