This does not affect remote content, only the content written in .astro files. If you have remote content you'd use something like `set:html`: https://docs.astro.build/en/reference/directives-reference/#...
See this example: https://stackblitz.com/edit/github-ug3paw61?file=src%2Fpages...
Unfortunately, I've also come across .astro files that I'm not allowed to touch and yet have to work with them (some internal corporate dinosaur which has not been updated for a while).
For my personal site, it was a 5 minute work, as usual :)