Please also enable CORS[1] for your RSS feed. (If your whole site is a static site, then please just enable CORS site-wide. This is how GitHub Pages works. There's pretty much no reason not to.)
Not having CORS set up for your RSS feed means that browser-based feed readers won't be able to fetch your feed to parse it (without running a proxy).
If you want to get a red line, you need to use red ink. If you use blue ink, you'll get blue lines. And I can draw you cat. (I'm no artist, but I can give it a try.) But it it won't be a line anymore. A line and a cat: those are two different things.
Not having CORS set up for your RSS feed means that browser-based feed readers won't be able to fetch your feed to parse it (without running a proxy).
1. <https://enable-cors.org/>