For instance: I've been using Astro with Svelte to build static sites with some components that require client-side interactivity. I really like that Astro doesn't ship any JS by default and just outputs static HTML, and when I want some page to have an interactive JS component, Svelte is an option that produces a relatively small amount of client JS.
But: Using Svelte with Astro this way for static sites has been broken since August 2025. As soon as you have a conditionally rendered child component in Svelte, Astro fails to bundle the styles for it in the static output of the site, and it does that ONLY in production, which is really devious, you could build a whole site (using astro dev) without knowing and then it breaks when you deploy it.
The issue is here: https://github.com/withastro/astro/issues/14252
I don't want to be complaining about how quickly issues get addressed in an OSS project that I'm not paying for, I don't blame them for not keeping tabs on every framework integration, I just would love to build websites with the latest versions Astro and Svelte, and I unfortunately have the feeling I should have just gone with SvelteKit for a smoother experience.