carla: Traffic Manager hangs after reload

Hello,

In the lastest version (0.9.9), client.get_trafficmanager() will hang if the world is reloaded and a traffic manager has been created with sync mode before. Am I missing something? A minimal example to reproduce this is

import carla

client = carla.Client('127.0.0.1', 2000)
world = client.load_world('Town01')
print ("Loaded world")

tm = client.get_trafficmanager()
tm.set_synchronous_mode(True)
print ("TM set to sync")

world = client.load_world('Town01')
print ("Loaded world")

tm = client.get_trafficmanager() # This will hang
print ("Got TM")

I am using Python 3.7 and Ubuntu 18.04.