This migration guide provides an overview of how to upgrade your system and applications based on the recent breaking changes. See the linked PRs for more detailed migration instructions. Use the migration script to migrate some of these automatically: npx svelte-migrate svelte-4
Upgrade to Node 16 or higher. Earlier versions are no longer supported. (#8566)
Upgrade to webpack 5 or higher. Earlier versions are no longer supported. (#8515)
Bundlers must now specify the browser condition when building a frontend bundle for the browser. (#8516)