# What's new in Svelte: June 2021

DevFeed: [What's new in Svelte: June 2021](<https://devfeed.tech/articles/what-s-new-in-svelte-june-2021-3092.md>)

Original publisher: [Read original article](<https://svelte.dev/blog/whats-new-in-svelte-june-2021>)

Author: Dani Sandoval

Published: 2021-06-01T00:00:00Z

Content type: release

Language: en

Sources: [Svelte blog](<https://devfeed.tech/sources/svelte-blog.md>)

Topics: [Svelte](<https://devfeed.tech/topics/svelte.md>), [Documentation](<https://devfeed.tech/topics/documentation.md>), [TypeScript](<https://devfeed.tech/topics/typescript.md>), [Vite](<https://devfeed.tech/topics/vite.md>), [JavaScript](<https://devfeed.tech/topics/javascript.md>), [Netlify](<https://devfeed.tech/topics/netlify.md>), [hosting](<https://devfeed.tech/topics/hosting.md>)

Tags: [bug-fixes](<https://devfeed.tech/tags/bug-fixes.md>), [docs](<https://devfeed.tech/tags/docs.md>), [hosting](<https://devfeed.tech/tags/hosting.md>), [javascript](<https://devfeed.tech/tags/javascript.md>), [netlify](<https://devfeed.tech/tags/netlify.md>), [release](<https://devfeed.tech/tags/release.md>), [svelte](<https://devfeed.tech/tags/svelte.md>), [typescript](<https://devfeed.tech/tags/typescript.md>), [updates](<https://devfeed.tech/tags/updates.md>), [vite](<https://devfeed.tech/tags/vite.md>)

## AI overview

A June 2021 update covering new SvelteKit features, bug fixes, and documentation, along with improvements to Svelte language tools. Highlights include ESM configuration loading, bundled Vite, trailing-slash configuration, router fixes, hydration fixes, and deeper TypeScript integration through a new plugin and VS Code extension updates.

## Source excerpt

This month, we saw lots of contributions to SvelteKit and its docs. The language tools also got some new features, most notably deeper integration with Svelte files within JavaScript or TypeScript files. Let's jump into the updates... New in SvelteKit svelte.config.js config files are now loaded in ESM format (.js instead of .cjs). AMP pages will now use the rendered CSS, rather than emitted CSS svelte-check has been added to the TypeScript template (sveltejs/kit#1556) Support for https keypair sveltejs/kit#1456 Now bundling Vite with SvelteKit and using an upgraded version. Remove Vite from your package.json if it's there Etags for binary responses sveltejs/kit#1382 Renamed $layout to __layout and $error to __error Removed getContext in favor of request.locals Renamed .svelte output directory to .svelte-kit. Update your .gitignore accordingly trailingSlash: 'never' | 'always' | 'ignore' is now available in the config. This should make it easier to build sites that work with static hosting providers that expect a trailing slash for index.html pages, and provides an escape hatch for anyone that needs more complex behaviour. Notable bug fixes in SvelteKit adapter-netlify got a fix sveltejs/kit#1467 and new documentation in the readme https://github.com/sveltejs/kit/tree/master/packages/adapter-netlify The router will no longer intercept navigation for URLs that the app does not own. This fixes a crash for apps that have <a> elements on the page with the same origin but don't share a base path with the app. Hash only changes are now handled by the router fixing the browser's "back" navigation between hash changes in some circumstances. New in Svelte & Language Tools Svelte 3.38.1 and 3.38.2 fixed an issue with hydration that was causing duplicate elements. If you're seeing this in your project, be sure to update the latest version! A new TypeScript plugin provides deeper integration with Svelte files within JavaScript or TypeScript files. This includes diagnostics, ref