Canvas rendering isn't that consistent, and when it goes weird it's often OS specific instead of merely browser specific. Some things I've run into: - OSX like

Canvas rendering isn't that consistent, and when it goes weird it's often OS specific instead of merely browser specific. Some things I've run into: - OSX likes to turn random Unicode symbols into emoji (extends past Canvas) - Fractional font sizes on Chrome/Linux get bizarrely stretched out (after a transform that makes the font not a fractional size) - Complex clipping operations freak Chrome out - All the compositing rendering options are broken somewhere or mis-defined to the point that it's weirdly hard to render anything to an alpha channel You also need input APIs to make a game, and the input APIs often have strange inconsistencies in function names, returned objects, or event ordering. Canvas is nice and straightforward if you want a purely sprite-based game with only mouse/keyboard input (but even then you need to jump through hoops if you want pixel art). Anything beyond that is going to need cross-platform debugging.