Introduce the the ability to use floating point pixel formats (as opposed to 8-bit fixed point) with CanvasRenderingContext2D, OffscreenCanvasRenderingContext2D, and ImageData. This is necessary for high precision applications (e.g, medical visualization), high dynamic range content, and linear working color spaces.
Floating-point pixel values are the natural representation of pixel data, and allow such features as representing colors in arbitrarily wide gamuts and high dynamic range. Current 2D canvases are limited to representing pixels using 8-bit unsigned integers, for historical reasons. All other canvas rendering APIs (WebGL and WebGPU) have floating-point pixel support. This brings 2D canvas rendering in line with the capabilities of all other APIs. This is also a prerequisite for enabling 2D canvas rendering to create HDR content.
Explainers: https://github.com/ccameron-chromium/ColorWeb-CG/blob/canvas2d_float/canvas_float.md