Windows Terminal seems to support WebP and AVIF background images... Strange, isn't it?

[skycommand]

So, most of you probably know that you can change a Terminal profile's background image via Settings > (Profile's name) > Appearance > Background image.

According to Terminal, the supported formats are JPEG, PNG, BMP, GIF, TIFF, and (for some weird reason) ICO. Today, I give Terminal that path to an AVIF image. To my surprise, Terminal opened it without a problem. I asked it to use a WebP image. That one was supported too.

So, why is this not an official feature? I've all but ditched the PNG format in favor of the Lossless WebP.