The battery tray indicators I’ve tried on Linux so far only seem to take the instantaneous power consumption into account. Is there one that estimates remaining battery life based on power draw over a longer time window and integrates easily with my desktop environment’s tray?
Not that I’m aware of
this would be a useful troubleshooting step and, since you’re already using xfce, you should be able to easily and temporarily switch your display manger to switch to something like gnome or kde to check.
if gnome shows battery correctly; then you know that it’s xfce and then you have you answer.
Not going after a bug though, it’s just the way the included battery meter in Xfce (and other X11 battery indicators I’ve found) works, while things like Android track usage over time to give a better estimate.
But based on the other responses, it looks like I’ll have to cook it up myself.