Some problems with the widget on Android 9.
Often the widget hangs after a reboot and the only way to fix it is to remove and re-add it to the screen. I think this happens when the network is not yet available, but I can't say for sure. Seems to happen 80% of the time.
wait until network is ready before getting weather data
if for some reason the network is not ready, allow the widget to recover from that
Then there's a UI problem with the "failed to retrieve data screen". If there is older data, this screen should disappear and the old weather data be displayed instead. There can still be a small warning icon that current data is not available, but the way it's now, the whole widget becomes useless when the internet connection is bad. That can be solved better. This is a notable problem, because otherwise the UI is very, very good. So:
cache old weather data
try to get new data
if successful, display new data
if not successful, display old data and warning icon