Consider EXT_shader_pixel_local_storage #3385
Description
In the WebGL WG conference call of 2022-02-10, the idea of exposing EXT_shader_pixel_local_storage was discussed.
The point was made that this is a least-common-denominator programmable blending extension, and can actually be implemented on top of EXT_shader_framebuffer_fetch, which is being rejected in #3378 .