On mobiles some WebGL demos have forced me to take out the battery, because I couldn't even kill the browser application or do the whole long button press for full restart.
Luckily I don't buy mobile phones that don't allow me to replace the battery.
If the hardware + OS are so deficient that your only way to stop a WebGL demo is to take out the battery, I'm not sure "lucky" is the word I'd use to describe your situation.
Capable of doing OpenGL ES 3.0 without sweating in native code and my usual test device for quality WebGL demos, always with the latest Chrome version.
Luckily I don't buy mobile phones that don't allow me to replace the battery.