Gallerys automatically keeping aspect ratio

I get this which has no filetype

https://www.wemyssweb.net/connectors/system/phpthumb.php?src=assets%252Fgallery%252F1%252F1.jpg&w=100&h=0&HTTP_MODAUTH=modx62b6de2683bbd9.54290183_16564e80c678d56.99027546&f=webp&q=90&wctx=mgr&source=1&t=1699038895&ar=x