Android Pie battery drain

I've been experiencing chronic battery drain since updating to Android Pie, attributed to Android System, Android OS, Google Play Services.

I've finally found the culprit: the Pebble app. Replaced with Gadgetbridge and all is well.

The cause seems to be abuse of Google Play Services and of WebView ('sandboxed_process0') causing significant drain while the phone is awake and contributing to drain while locked. Probably underpinning features nobody asked for, like the Javascript SDK, PebbleKit, location-based weather, Pebble internet connectivity, etc. Gadgetbridge excludes all of that nonsense by design or as an option, don't know why I didn't switch sooner!

And as a handy side effect, phone calls no longer show up as from Unknown!