This proposal introduces a new API for rendering HTML content within a <canvas> element. The API includes the layoutsubtree attribute, drawElementImage() method, and paint event, enabling better accessibility, internationalization, and performance for canvas-based content. The proposal also addresses the need for exporting HTML content as images or video.

The drawElementImage API allows for drawing element image snapshots onto a canvas, with considerations for privacy and security to prevent leaking sensitive information. The paint event is introduced to notify developers of paint changes, allowing for canvas rendering updates in sync with the DOM. Future considerations include supporting threaded effects with an auto-updating canvas mode.