As far as I remember, it's down to security concerns.
You can actually insert your HTML into a SVG foreignObject, and then drawImage() that onto your canvas. But your HTML-in-SVG document will need to load all its own resources, fonts, CSS etc.. which makes this process rather tedious.
You can actually insert your HTML into a SVG foreignObject, and then drawImage() that onto your canvas. But your HTML-in-SVG document will need to load all its own resources, fonts, CSS etc.. which makes this process rather tedious.