svelte Releases

This patch release focuses on stabilizing Server-Side Rendering (SSR) by fixing validation for `svelte:element` tags, escaping of special characters in options, and the removal of event handlers during the render process.

Feb 18, 2026

A maintenance release that improves performance by proactively deferring effects in pending boundaries and introduces stricter checks to detect and error on non-idempotent keys in `each` blocks during development.

Feb 18, 2026

This release addresses event delegation conflicts between multiple Svelte instances, adjusts CSS attribute selectors to be case-insensitive for HTML enumerated attributes, and ensures effects run correctly in pending snippets.

Feb 17, 2026

Focused on async handling, this patch updates dev delegated handlers to properly account for asynchronous operations and adds a warning for props that are referenced locally without destructuring.

Feb 15, 2026

A stability patch that prevents crashes related to undefined `document.contentType` and improves event delegation encapsulation by using symbols to prevent namespace pollution.

Feb 14, 2026

This minor release introduces `TrustedTypes` support for secure HTML handling where supported and includes fixes for sanitizing template literal special characters in SSR attribute values.

Feb 13, 2026

Focusing on XHTML compliance, this release handles case sensitivity for node names and specific attributes, manages derived effect lifecycles by freezing them when disconnecting, and improves error propagation to `<svelte:boundary>`.

Feb 12, 2026

This patch resolves hydration issues specifically related to `bind:value` on `<select>` elements with derived state in legacy mode and prevents swallowing of `DOMException` errors when media playback fails.

Feb 11, 2026

A maintenance release that ensures XHTML compliance by rendering boolean attribute values as empty strings and prevents hydration mismatches in async render tags.

Feb 10, 2026

This minor release enables programmatic component instantiation using `createContext` and fixes hydration logic to handle edge cases such as `{#key NaN}` and properly hydrate already-resolved async blocks.

Feb 6, 2026

This patch release focuses on bug fixes for async operations, Cloudflare compatibility, and internal type definitions.

Feb 4, 2026

A maintenance patch addressing SSR optimizations, text node handling, and promise management within script tags.

Jan 30, 2026

This minor release introduces a new customization option for custom elements and numerous stability fixes for effects, reactivity, and transitions.

Jan 29, 2026

A patch release fixing error handling boundaries, namespace export issues, and complex rendering logic involving effects in each blocks.

Jan 28, 2026

A small patch focused on correcting CSS parsing to prevent character duplication in the Abstract Syntax Tree.

Jan 27, 2026

A patch release improving SSR hydration stability, accessibility warnings, and dynamic component handling.

Jan 26, 2026

A minor patch that exposes a utility function previously available internally for external use.

Jan 24, 2026

A patch release heavily focused on optimizing async operations, code generation, and hydration logic.

Jan 24, 2026

A minor release exposing a CSS parser utility and improving type safety for element rendering.

Jan 22, 2026

A patch release ensuring reactivity updates correctly for the `selectedcontent` property.

Jan 19, 2026