Basic summary: The canvas API is the wrong target for making bespin accessible. What needs to be made accessible is its widget toolkit, not the way it draw the widgets to the screen. How do we do that?

Nobody complains about CSS not being accessible. Why is that? I think canvas belongs firmly in the “Presentation” teir of the webstack, sitting right next to CSS. what’s missing is not some feature of the Canvas API, but the ability to expose Bespin’s object model to an accessable client without having to construct essentially a hidden and duplicated HTML DOM. What else is missing? A design that makes creating accessible apps useful to developers that are not disabled in some way.