Much to my delighted surprise, it renders very smoothly in Firefox 45 on this rather resource-constrained machine, in a way that stuff like this almost never does.
I was also surprised at how it appeared to run at full frame rate on my aging iPhone 6
Great now I am sad because my phone is considered old :P
iPhone 6's are considered old these days? Yeesh. I thought they were still fairly powerful for a mobile device.
If they got it when it was originally released it's 2 years old now which is pretty old for any electronics in terms of where it'd sit on the performance curve.
It's in the top end of the performance spectrum still.