Zigbee2mqtt : strange logs

Can, please, someone explain the meaning of these two lines in my zigbee2mqtt log ?

gen 20 11:18:25 raspberrypi npm[13853]: zigbee2mqtt:debug 2019-1-20 11:18:25 Received zigbee message of type 'devChange' with data '{"cid":"genBasic","data":{"65281":[null,null,null,35,null,34,null,"0x0000000000000000",4896,1026,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,1,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,8.657529830932617,null,null,4.900000095367432,null,16]}}' of device 'lumi.plug' (0x00158d0001bc2dbe)

gen 20 11:19:27 raspberrypi npm[13853]: zigbee2mqtt:debug 2019-1-20 11:19:27 Received zigbee message of type 'devChange' with data '{"cid":"genBasic","data":{"65281":[null,3005,null,22,17320,191,[0,1],null,null,null,41025,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,0,92,56,4]}}' of device 'lumi.sensor_cube' (0x00158d00028af49c)

Thanks