Well ofc and I know some elisp but I take it integrating libjxl (now using the "new BSD license") or another library supporting jxl is one of those things requi

Well ofc and I know some elisp but I take it integrating libjxl (now using the "new BSD license") or another library supporting jxl is one of those things requiring C guru skills. And it's been a really long time I haven't written a line of C code. Moreover I take it that, say, for someone who added WEBP support to Emacs, adding JPEG XL would be kinda a no-brainer. But I fully get your point...