A few misbehaving CSS filters can make my discreet GPU turn on and at that point my battery life is a goner. Not sure who to blame in that scenario.
There was an old bug in FF around 2018 where a tab using a GPU would prevent a Windows laptop from ever sleeping. That ended up destroying that laptop's battery after it got thrown in my backpack and overheated a couple times.
Seems like this could be fixed by a system setting that disables automatic graphic switching which can be controlled by power profiles. That way the user can set the machine to use iGPU only when on battery, regardless of what programs want.
There was an old bug in FF around 2018 where a tab using a GPU would prevent a Windows laptop from ever sleeping. That ended up destroying that laptop's battery after it got thrown in my backpack and overheated a couple times.