ref: 115edab4597ba526f9afaa659e4c968db026658f
parent: a6a799720f53d52721284c201e2dfc81610c2e40
author: Ben Harris <bjh21@bjh21.me.uk>
date: Fri Nov 25 14:13:43 EST 2022
js: Remove alpha channel from almost all our canvases
Specifying the { alpha: false } option when creating a rendering context
tells the browser that we won't use transparency, and the standard
puzzle canvases, along with blitters, are all opaque. No obvious
effect, but the MDN suggests that this should reduce CPU usage.
The one exception here is the resize handle, which actually is
transparent.