I don’t know what a .webp file is but I don’t like it. They’re like a filthy prank version of the image/gif you’re looking for. They make you jump through all these hoops to find the original versions of the files that you can actually do anything with.
Confusingly, XL doesn’t stand for “eXtra Large”. JPEG has had multiple standards over the years, many of which start with X. In this context, the L in XL means Long-term. As in, they expect this format to last a long time like the original JPEG we all know and “love” has.
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That’s makes sense, I can’t shake the extra large connotations on XL :P