Perhaps you all know this, but I didn't

Silly me, I assumed MOST chargers do not discharge the battery if the power is disconnected, however, that is not the case with the OSMO charger.
Mine got disconnected, it still had the green light on, but that was because it was discharging the battery and not a full charge.  So, I too the battery with me, put it in the Osmo and I had 2% battery left!


Yea, it was silly that the plug was disconnected, but I didnt think the charger would then kill the battery

oh well.  Live and Learn

Bruce

Glad you figured this out. It's implied in the user manual,