The Shadow DOM is a browser feature that encapsulates a component's DOM and styles, preventing them from affecting the rest of the document. While Svelte does not use the Shadow DOM by default, it can work with it if needed.
Svelte achieves style and DOM encapsulation by generating scoped CSS classes and avoiding global leaks, providing many benefits of Shadow DOM without actually using it.
You can manually attach a Svelte component to a shadow root by creating a custom element and mounting it to a shadow DOM. This is useful for web components or library distribution.
Svelte's scoped styles already provide encapsulation in most cases.
Using Shadow DOM may affect CSS inheritance and global styles.
Browser support for Shadow DOM is good, but older browsers may require polyfills.
Custom elements with Shadow DOM are useful for distributing reusable components outside Svelte apps.