Major Changes

• #16965 57ead0d Thanks @Princesseuh! - Makes 'jsx' the default value for compressHTML

  Astro now strips whitespace from your HTML using JSX rules by default, the same way frameworks like React do. Whitespace and line breaks around elements are removed, but meaningful whitespace within a single line — like a space between two inline elements — is preserved. To keep a space that would otherwise be removed, write it explicitly in your source, for example with {" "}.

  This can change rendered output where whitespace between inline elements was previously meaningful. To keep Astro's earlier behavior, set compressHTML: true for HTML-aware compression, or compressHTML: false to preserve all whitespace.

Patch Changes

• #17111 c0f33ed Thanks @ematipico! - Harden the limits on the number of decoding on the URL.

• #17095 e84ebc0 Thanks @matthewp! - Improves build performance by removing an unfiltered transform hook from the astro:head-metadata-build plugin. Head propagation modules are now identified by their module ID (?astroPropagatedAssets) instead of scanning every module's source code.

• #17041 4c4a91c Thanks @iseraph-dev! - Fixes a bug where the advanced routing astro/hono / astro/fetch pages() handler returned the host framework's default Internal Server Error response instead of rendering the custom 500.astro page when a page threw during render. Unmatched requests with a prerendered (or absent) custom 404 page now render the 404 error page instead of failing the same way.

• #17097 5e340d7 Thanks @iseraph-dev! - Fixes a bug where the advanced routing astro/hono / astro/fetch middleware() handler returned the host framework's default Internal Server Error response instead of rendering the custom 500.astro page when middleware threw. Unmatched requests with a prerendered (or absent) custom 404 page now render the 404 error page instead of failing the same way. Errors surfaced through next (the host framework's downstream chain) still propagate to the host's own error handler.

• #17104 b074a37 Thanks @iseraph-dev! - Fixes the custom 500.astro page receiving an empty error prop when the error originated in middleware.

• #17098 637a1b6 Thanks @matthewp! - Fixes internal Astro headers leaking from direct pages() handler responses