Re-apply a0b1b34c71e46304f7024f0570db92f4577303b5 to master (fixing synctl)
Re-apply a0b1b34c71e46304f7024f0570db92f4577303b5 to master (fixing synctl)

matrix-org/synapse,illicitonion/synapse,TribeMedia/synapse,illicitonion/synapse,TribeMedia/synapse,howethomas/synapse,iot-factory/synapse,illicitonion/synapse,iot-factory/synapse,illicitonion/synapse,rzr/synapse,rzr/synapse,iot-factory/synapse,TribeMedia/synapse,iot-factory/synapse,illicitonion/synapse,matrix-org/synapse,TribeMedia/synapse,rzr/synapse,iot-factory/synapse,howethomas/synapse,TribeMedia/synapse,rzr/synapse,matrix-org/synapse,matrix-org/synapse,howethomas/synapse,matrix-org/synapse,howethomas/synapse,howethomas/synapse,matrix-org/synapse,rzr/synapse