diff --git a/packages/runtime-playground/src/editor-command-runners.ts b/packages/runtime-playground/src/editor-command-runners.ts
index c6a12cd8..12ffff36 100644
--- a/packages/runtime-playground/src/editor-command-runners.ts
+++ b/packages/runtime-playground/src/editor-command-runners.ts
@@ -853,6 +853,7 @@ interface EditorPresentationCapture {
   canvasDocumentType: "iframe" | "parent"
   iframeCount: number
   stylesheetUrls: string[]
+  loadedStylesheetUrls: string[]
   inlineStyleContents: string[]
 }
 
@@ -872,12 +873,14 @@ function externalStylesheetPresentationIdentity(url: string): string | undefined
 
 export function summarizeEditorPresentation(capture: EditorPresentationCapture, expectedIdentities: readonly string[] = []): BrowserEditorPresentationSummary {
   const iframeStylesheetUrls = [...new Set(capture.stylesheetUrls.map((url) => url.trim()).filter(Boolean))].sort()
+  const loadedStylesheetUrls = new Set(capture.loadedStylesheetUrls.map((url) => url.trim()).filter(Boolean))
   const inlineIdentities = capture.inlineStyleContents.flatMap((content) => [...content.matchAll(/blocks-engine-presentation:([a-f0-9]{64})/gi)].map((match) => match[1]!.toLowerCase()))
   // Only an expected identity can be certified from a URL version. An
   // unrequested or arbitrary version stays out of the observed set so the
   // expected-set comparison remains fail-closed.
   const expected = new Set(expectedIdentities.map((identity) => identity.trim().toLowerCase()).filter(Boolean))
   const externalIdentities = iframeStylesheetUrls.flatMap((url) => {
+    if (!loadedStylesheetUrls.has(url)) return []
     const identity = externalStylesheetPresentationIdentity(url)
     return identity && expected.has(identity) ? [identity] : []
   })
@@ -928,6 +931,9 @@ export async function captureEditorPresentation(page: import("playwright").Page,
         canvasDocumentType,
         iframeCount,
         stylesheetUrls: stylesheets.flatMap((stylesheet) => stylesheet.href ? [stylesheet.href] : []),
+        // A link is not proof of delivery: failed stylesheet requests leave
+        // sheet unset and must not satisfy an expected presentation identity.
+        loadedStylesheetUrls: stylesheets.flatMap((stylesheet) => stylesheet.href && stylesheet.sheet ? [stylesheet.href] : []),
         inlineStyleContents: Array.from(document.querySelectorAll("style"), (style) => style.textContent ?? ""),
       }
     }, { canvasDocumentType, iframeCount: canvasDocumentType === "iframe" ? 1 : 0 }).catch(() => null) as (EditorPresentationCapture & { documentIdentity: string; documentAgeMs: number }) | null
@@ -995,13 +1001,6 @@ if ( ! function_exists( 'set_current_screen' ) ) {
   require_once ABSPATH . 'wp-admin/includes/screen.php';
 }
 set_current_screen( 'post' );
-$wp_styles = wp_styles();
-wp_scripts();
-$queued_before_editor_assets = $wp_styles->queue;
-do_action( 'enqueue_block_assets' );
-$editor_style_handles = array_values( array_diff( $wp_styles->queue, $queued_before_editor_assets ) );
-$wp_styles->all_deps( $editor_style_handles );
-$editor_style_handles = array_values( array_unique( array_merge( $editor_style_handles, $wp_styles->to_do ) ) );
 $settings = get_block_editor_settings( array(), new WP_Block_Editor_Context( array( 'post' => $post ) ) );
 $identities = array();
 foreach ( (array) ( $settings['styles'] ?? array() ) as $style ) {
@@ -1010,10 +1009,19 @@ foreach ( (array) ( $settings['styles'] ?? array() ) as $style ) {
     foreach ( $matches[1] as $identity ) { $identities[] = strtolower( $identity ); }
   }
 }
-foreach ( $editor_style_handles as $handle ) {
-  $style = $wp_styles->registered[$handle] ?? null;
-  $version = is_object( $style ) ? ( $style->ver ?? null ) : null;
-  if ( is_string( $version ) && preg_match( '/^[a-f0-9]{64}$/iD', $version ) ) { $identities[] = strtolower( $version ); }
+// WordPress collects iframe assets in an isolated styles instance, so the
+// resolved asset HTML is the authoritative external stylesheet contract.
+$resolved_styles = (string) ( $settings['__unstableResolvedAssets']['styles'] ?? '' );
+if ( preg_match_all( '~<link\\b[^>]*\\bhref=([^[:space:]>]+)~i', $resolved_styles, $links ) ) {
+  foreach ( $links[1] as $href ) {
+    $url = trim( html_entity_decode( $href, ENT_QUOTES, 'UTF-8' ), chr(34) . chr(39) );
+    $query = wp_parse_url( $url, PHP_URL_QUERY );
+    if ( ! is_string( $query ) ) { continue; }
+    parse_str( $query, $parameters );
+    $version = $parameters['ver'] ?? null;
+    if ( is_array( $version ) ) { continue; }
+    if ( is_string( $version ) && preg_match( '/^[a-f0-9]{64}$/iD', $version ) ) { $identities[] = strtolower( $version ); }
+  }
 }
 $identities = array_values( array_unique( $identities ) );
 sort( $identities, SORT_STRING );
diff --git a/tests/editor-actions.test.ts b/tests/editor-actions.test.ts
index 19295c55..40f2d37e 100644
--- a/tests/editor-actions.test.ts
+++ b/tests/editor-actions.test.ts
@@ -72,6 +72,7 @@ const styledPresentation = summarizeEditorPresentation({
   canvasDocumentType: "iframe",
   iframeCount: 2,
   stylesheetUrls: ["https://example.test/styles/editor.css", "https://example.test/styles/editor.css", "https://example.test/styles/theme.css"],
+  loadedStylesheetUrls: ["https://example.test/styles/editor.css", "https://example.test/styles/theme.css"],
   inlineStyleContents: [
     "/* blocks-engine-presentation:ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789 */",
     "/* blocks-engine-presentation:abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789 */",
@@ -86,7 +87,7 @@ assert.deepEqual(styledPresentation, {
   generatedPresentationIdentityCount: 1,
   generatedPresentationIdentities: ["abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789"],
 })
-assert.deepEqual(summarizeEditorPresentation({ canvasDocumentType: "parent", iframeCount: 0, stylesheetUrls: [], inlineStyleContents: [".editor { color: black; }"] }), {
+assert.deepEqual(summarizeEditorPresentation({ canvasDocumentType: "parent", iframeCount: 0, stylesheetUrls: [], loadedStylesheetUrls: [], inlineStyleContents: [".editor { color: black; }"] }), {
   schema: "wp-codebox/editor-presentation/v1",
   canvasDocumentType: "parent",
   iframeCount: 0,
@@ -106,6 +107,7 @@ const externalOnlyPresentation = summarizeEditorPresentation({
   canvasDocumentType: "iframe",
   iframeCount: 1,
   stylesheetUrls: [`https://example.test/wp-content/themes/fixture/assets/a.css?ver=${externalIdentityA.toUpperCase()}`],
+  loadedStylesheetUrls: [`https://example.test/wp-content/themes/fixture/assets/a.css?ver=${externalIdentityA.toUpperCase()}`],
   inlineStyleContents: [],
 }, [externalIdentityA])
 assert.deepEqual(externalOnlyPresentation.generatedPresentationIdentities, [externalIdentityA], "expected external stylesheet version certifies its identity")
@@ -117,6 +119,7 @@ assert.deepEqual(summarizeEditorPresentation({
   canvasDocumentType: "iframe",
   iframeCount: 1,
   stylesheetUrls: [`https://example.test/a.css?ver=${externalIdentityA}`, `https://example.test/b.css?ver=${externalIdentityB}`],
+  loadedStylesheetUrls: [`https://example.test/a.css?ver=${externalIdentityA}`, `https://example.test/b.css?ver=${externalIdentityB}`],
   inlineStyleContents: [`:root{--blocks-engine-presentation:${inlineIdentity};}`],
 }, [externalIdentityA, externalIdentityB]).generatedPresentationIdentities, [externalIdentityA, externalIdentityB, inlineIdentity].sort(), "inline and external identities combine")
 
@@ -130,23 +133,30 @@ assert.deepEqual(summarizeEditorPresentation({
     "https://example.test/b.css?ver=6.7.1",
     "https://example.test/c.css",
   ],
+  loadedStylesheetUrls: [
+    `https://example.test/a.css?ver=${unrequestedIdentity}`,
+    "https://example.test/b.css?ver=6.7.1",
+    "https://example.test/c.css",
+  ],
   inlineStyleContents: [],
 }, [externalIdentityA]).generatedPresentationIdentities, [], "unrequested and non-hash versions are not identities")
 assert.deepEqual(summarizeEditorPresentation({
   canvasDocumentType: "iframe",
   iframeCount: 1,
   stylesheetUrls: [`https://example.test/a.css?ver=${externalIdentityA}`],
+  loadedStylesheetUrls: [`https://example.test/a.css?ver=${externalIdentityA}`],
   inlineStyleContents: [],
 }).generatedPresentationIdentities, [], "no expected set certifies no external identity")
 
-// A delayed stylesheet that has not yet appeared leaves the expected identity
-// unobserved rather than reporting it as satisfied.
+// A failed stylesheet stays visible in the evidence but cannot certify an
+// expected identity.
 assert.deepEqual(summarizeEditorPresentation({
   canvasDocumentType: "iframe",
   iframeCount: 1,
   stylesheetUrls: [`https://example.test/a.css?ver=${externalIdentityA}`],
+  loadedStylesheetUrls: [],
   inlineStyleContents: [],
-}, [externalIdentityA, externalIdentityB]).generatedPresentationIdentities, [externalIdentityA], "a not-yet-loaded stylesheet stays unobserved")
+}, [externalIdentityA, externalIdentityB]).generatedPresentationIdentities, [], "a failed stylesheet stays unobserved")
 
 const idleCanvas = await captureEditorIdleCanvas({
   evaluate: async (callback: () => unknown) => {
diff --git a/tests/editor-presentation-contract.test.ts b/tests/editor-presentation-contract.test.ts
index aea1cb34..81ed6802 100644
--- a/tests/editor-presentation-contract.test.ts
+++ b/tests/editor-presentation-contract.test.ts
@@ -7,9 +7,8 @@ import { runCommandText } from "../scripts/test-kit.js"
 
 const inlineIdentity = "A".repeat(64)
 const externalIdentity = "b".repeat(64)
-const unrelatedIdentity = "c".repeat(64)
 
-async function captureContract(inlineCss: string[], editorVersions: unknown[], prequeuedVersions: unknown[] = []): Promise<{ identities: string[]; complete: boolean }> {
+async function captureContract(inlineCss: string[], resolvedStylesheetUrls: string[]): Promise<{ identities: string[]; complete: boolean }> {
   const root = await mkdtemp(join(tmpdir(), "wp-codebox-editor-presentation-"))
   const includes = join(root, "wp-admin", "includes")
   await mkdir(includes, { recursive: true })
@@ -20,33 +19,13 @@ define( 'ABSPATH', ${JSON.stringify(`${root}/`)} );
 class WP_Post {}
 class WP_Block_Editor_Context { public function __construct( public array $context ) {} }
 $fixture_inline_css = ${JSON.stringify(inlineCss)};
-$fixture_editor_versions = ${JSON.stringify(editorVersions)};
-$fixture_prequeued_versions = ${JSON.stringify(prequeuedVersions)};
-$fixture_styles = new class {
-  public array $queue = array();
-  public array $registered = array();
-  public array $to_do = array();
-  public function all_deps( $handles ) { $this->to_do = $handles; }
-};
-foreach ( $fixture_prequeued_versions as $index => $version ) {
-  $handle = 'unrelated-' . $index;
-  $fixture_styles->queue[] = $handle;
-  $fixture_styles->registered[$handle] = (object) array( 'ver' => $version );
-}
-function get_post( $post_id ) { return new WP_Post(); }
-function wp_styles() { return $GLOBALS['fixture_styles']; }
-function wp_scripts() {}
-function do_action( $hook ) {
-  if ( 'enqueue_block_assets' !== $hook ) return;
-  foreach ( $GLOBALS['fixture_editor_versions'] as $index => $version ) {
-    $handle = 'editor-' . $index;
-    $GLOBALS['fixture_styles']->queue[] = $handle;
-    $GLOBALS['fixture_styles']->registered[$handle] = (object) array( 'ver' => $version );
+  $fixture_resolved_stylesheet_urls = ${JSON.stringify(resolvedStylesheetUrls)};
+  function get_post( $post_id ) { return new WP_Post(); }
+  function wp_parse_url( $url, $component = -1 ) { return parse_url( $url, $component ); }
+  function get_block_editor_settings( $settings, $context ) {
+   $links = implode( '', array_map( static fn ( $url ) => '<link rel="stylesheet" href="' . htmlspecialchars( $url, ENT_QUOTES, 'UTF-8' ) . '">', $GLOBALS['fixture_resolved_stylesheet_urls'] ) );
+   return array( 'styles' => array_map( static fn ( $css ) => array( 'css' => $css ), $GLOBALS['fixture_inline_css'] ), '__unstableResolvedAssets' => array( 'styles' => $links ) );
   }
-}
-function get_block_editor_settings( $settings, $context ) {
-  return array( 'styles' => array_map( static fn ( $css ) => array( 'css' => $css ), $GLOBALS['fixture_inline_css'] ) );
-}
 function wp_json_encode( $value ) { return json_encode( $value ); }
 ${editorPresentationContractPhpCode(17)}
 `
@@ -63,7 +42,7 @@ assert.deepEqual(await captureContract([`:root{--blocks-engine-presentation:${in
   complete: true,
 }, "inline-only delivery remains in the expected contract")
 
-assert.deepEqual(await captureContract([], [externalIdentity.toUpperCase()]), {
+assert.deepEqual(await captureContract([], [`https://example.test/editor.css?ver=${externalIdentity.toUpperCase()}`]), {
   identities: [externalIdentity],
   complete: true,
 }, "external-only editor delivery contributes its canonical version identity")
@@ -71,12 +50,12 @@ assert.deepEqual(await captureContract([], [externalIdentity.toUpperCase()]), {
 assert.deepEqual(await captureContract([
   `/* --blocks-engine-presentation:${inlineIdentity} */`,
   `/* --blocks-engine-presentation:${externalIdentity} */`,
-], [externalIdentity.toUpperCase()]), {
+], [`https://example.test/editor.css?ver=${externalIdentity.toUpperCase()}`]), {
   identities: [inlineIdentity.toLowerCase(), externalIdentity].sort(),
   complete: true,
 }, "mixed delivery is normalized, deduplicated, and sorted")
 
-assert.deepEqual(await captureContract([], ["6.7.1", "not-a-hash", ` ${externalIdentity}`, `${externalIdentity}0`, null], [unrelatedIdentity]), {
+assert.deepEqual(await captureContract([], ["https://example.test/a.css?ver=6.7.1", "https://example.test/b.css?ver=not-a-hash", `https://example.test/c.css?ver=%20${externalIdentity}`, `https://example.test/d.css?ver=${externalIdentity}0`]), {
   identities: [],
   complete: true,
 }, "non-hash versions and unrelated prequeued stylesheets are ignored")