fix(render): strip image preload links with imagesrcset or imagesizes when as=image is omitted

.changeset/strip-image-preload-imagesrcset.md

@@ -0,0 +1,5 @@
+---
+"@react-email/render": patch
+---
+
+Strip image preload links that carry `imagesrcset` or `imagesizes` without `as="image"`, so React-injected responsive-image hints no longer leak into rendered email HTML.

packages/render/src/shared/utils/strip-image-preload-links.spec.ts

@@ -24,6 +24,13 @@ describe('stripImagePreloadLinks()', () => {
     expect(stripImagePreloadLinks(html)).toBe('<head></head>');
   });
 
+  it('removes image preloads with imagesrcset or imagesizes when as="image" is omitted', () => {
+    const html =
+      '<head><link rel="preload" imagesrcset="logo.png 2x"/><link rel="preload" imagesizes="100vw"/></head>';
+
+    expect(stripImagePreloadLinks(html)).toBe('<head></head>');
+  });
+
   it('keeps user-authored non-image preloads', () => {
     const html =
       '<head><link rel="preload" as="style" href="styles.css"/><link rel="preload" as="font" href="font.woff2"/></head>';

packages/render/src/shared/utils/strip-image-preload-links.ts

@@ -21,7 +21,12 @@ export const stripImagePreloadLinks = (html: string): string => {
 
 const isImagePreloadLink = (tag: string): boolean => {
   const attributes = parseAttributes(tag);
-  return attributes.rel === 'preload' && attributes.as === 'image';
+  return (
+    attributes.rel === 'preload' &&
+    (attributes.as === 'image' ||
+      'imagesrcset' in attributes ||
+      'imagesizes' in attributes)
+  );
 };
 
 const ATTRIBUTE_PATTERN =