Performance gains from bundling JS and CSS sources in HTML are extreme and visible to users immediately on page load.
This plugin should be used for code that applies custom theming, fonts, dark mode and CSS that curbs awkward
flash of unstyled content
before any network requests for CSS complete.
Alternative approaches
There are Vite plugins for inlining sources in HTML that focus on inlining all sources into a single file.
Plugins that make HTML files without external dependencies are useful for embedded systems and
mobile apps. Check out
vite-plugin-singlefile for those use cases.
Without type="module" the script will be read from disk and inlined as-is.
JavaScript with type="module" will use esbuild.build and bundle all imports in the script output and the script tag
will include the type="module" attribute.
TypeScript inlining will use esbuild.build to bundle the script and any of its imports.
don't forget type="module" if you use top-level-await or any other ESM module features
CSS will be inlined as-is with a read of the file from your project directory.
Currently, nothing is done for @import within your CSS. Imported CSS could be bundled during inlining by using
lightningcss.