@petro I am using the code you posted, I am not getting startup errors either, but am still getting
2019-03-10 11:36:06 WARNING (SyncWorker_11) [custom_components.waze_travel_time.sensor] Error on retrieving data: empty response
2019-03-10 11:36:06 WARNING (SyncWorker_18) [custom_components.waze_travel_time.sensor] Error on retrieving data: empty response
2019-03-10 11:36:06 WARNING (SyncWorker_16) [custom_components.waze_travel_time.sensor] Error on retrieving data: empty response
2019-03-10 11:36:06 WARNING (SyncWorker_10) [custom_components.waze_travel_time.sensor] Error on retrieving data: empty response
2019-03-10 11:36:06 WARNING (SyncWorker_15) [custom_components.waze_travel_time.sensor] Error on retrieving data: empty response
about every 10 minutes so far. I have 5 sensors all of which use a device tracker for at either origin or destination
Edit: I will say that is did fix another error that has been bugging me for months. Iāve had issues where waze calculates my distance in KM even though Iām in US, selected US, and have imperial units set in HA.