BJS2, drop in battery life since update

The Power Manager app has a logging feature:

You can switch on logging in the options to diagnose unexpected power use. Currently the logging can capture the code running from timeouts and intervals and the power up and down of some devices. The captured times are probably not perfect but should be good enough to indicate problems.

You might find something out with that :)

Edit: there's also this: https://www.espruino.com/Reference#l_E_g­etPowerUsage