I noticed when a site has asset optimization on but with all options off (which in theory means it does nothing), there’s still some optimization occurring which breaks CSS with “url(#hash)” values. It may also break CSS in other conditions, but I’ve only tested in the conditions below.
I’ve created two proof of concept sites to show the issue. The first site has asset optimization “on” but all options unchecked.
The second site demonstrates expected behavior, which is to keep url(#hash) instead of “optimizing” it into the CDN.
I didn’t notice this issue during the day on September 2nd or before, so it seems to be something introduced late yesterday (Sept. 2nd) or sometime today (Sept. 3rd).
This also affects production sites, such as https://www.sarasoueidan.com/demos/css-svg-clipping/html-img-clipped-with-css-svg-clippath/
Let me know if you need more info or have any questions.