diff --git a/packages/blocks-engine/src/wp/__tests__/video-grid-layout.test.ts b/packages/blocks-engine/src/wp/__tests__/video-grid-layout.test.ts
new file mode 100644
index 000000000..de22dc2f2
--- /dev/null
+++ b/packages/blocks-engine/src/wp/__tests__/video-grid-layout.test.ts
@@ -0,0 +1,43 @@
+import { expect, it } from 'vitest';
+import { chromium } from 'playwright';
+import { execFileSync } from 'node:child_process';
+import { readFileSync } from 'node:fs';
+import { createRequire } from 'node:module';
+import { fileURLToPath } from 'node:url';
+
+const require = createRequire(import.meta.url) as { (id: string): any; resolve(id: string): string };
+const root = fileURLToPath(new URL('../../../../../php-transformer/', import.meta.url));
+
+it('retains source text/video grid geometry at 390, 768 and 1440px', async () => {
+  const source = readFileSync(`${root}/tests/fixtures/text-video-grid.html`, 'utf8');
+  const output = JSON.parse(execFileSync('php', ['-r', `
+    require 'vendor/autoload.php';
+    $r = (new Automattic\\BlocksEngine\\PhpTransformer\\HtmlToBlocks\\HtmlTransformer())->transform(file_get_contents('tests/fixtures/text-video-grid.html'))->toArray();
+    echo json_encode(['html' => $r['serialized_blocks'], 'css' => implode("\\n", array_column($r['assets'], 'content'))]);
+  `], { cwd: root, encoding: 'utf8' })) as { html: string; css: string };
+  const coreCss = readFileSync(require.resolve('@wordpress/block-library/build-style/style.css'), 'utf8');
+  const browser = await chromium.launch({ headless: true });
+  try {
+    const page = await browser.newPage();
+    for (const width of [390, 768, 1440]) {
+      await page.setViewportSize({ width, height: 1000 });
+      const measure = async (html: string) => {
+        await page.setContent(html);
+        return page.evaluate(() => ['h2', 'video'].map((selector) => {
+          const box = document.querySelector(selector)!.getBoundingClientRect();
+          return { x: box.x, y: box.y, width: box.width, height: box.height };
+        }));
+      };
+      const before = await measure(source);
+      const after = await measure(`<!doctype html><style>${coreCss}\n${output.css}</style>${output.html}`);
+      console.log(width, { source: before, imported: after });
+      for (const [index, box] of after.entries()) {
+        for (const key of ['x', 'y', 'width', 'height'] as const) {
+          expect(Math.abs(box[key] - before[index][key]), `${width}px ${index} ${key}`).toBeLessThan(1);
+        }
+      }
+    }
+  } finally {
+    await browser.close();
+  }
+}, 30000);
diff --git a/packages/blocks-engine/src/wp/__tests__/video-grid-save-validity.test.ts b/packages/blocks-engine/src/wp/__tests__/video-grid-save-validity.test.ts
new file mode 100644
index 000000000..c09a67e86
--- /dev/null
+++ b/packages/blocks-engine/src/wp/__tests__/video-grid-save-validity.test.ts
@@ -0,0 +1,49 @@
+import { beforeAll, describe, expect, it, vi } from 'vitest';
+import { execFileSync } from 'node:child_process';
+import { createRequire } from 'node:module';
+import { fileURLToPath } from 'node:url';
+import { setupDomGlobals } from '../dom-globals.js';
+
+const require = createRequire(import.meta.url) as { (id: string): any; resolve(id: string): string };
+type Block = { name: string; innerBlocks: Block[]; attributes: Record<string, unknown> };
+type Wp = {
+  parse(markup: string): Block[];
+  validateBlock(block: Block): [boolean, unknown[]];
+};
+const transformer = fileURLToPath(new URL('../../../../../php-transformer/', import.meta.url));
+
+describe('text/video author grid Gutenberg save validity', () => {
+  let wp: Wp;
+  beforeAll(() => {
+    setupDomGlobals();
+    wp = require('@wordpress/blocks') as Wp;
+    require('@wordpress/block-library').registerCoreBlocks();
+  });
+
+  it('detects the former media-text video attribute mismatch', () => {
+    const error = vi.spyOn(console, 'error').mockImplementation(() => undefined);
+    const warn = vi.spyOn(console, 'warn').mockImplementation(() => undefined);
+    try {
+      const blocks = wp.parse('<!-- wp:media-text {"mediaType":"video"} --><div class="wp-block-media-text is-stacked-on-mobile"><figure class="wp-block-media-text__media"><video controls src="clip.mp4" poster="poster.jpg" preload="metadata" loop="loop" muted="muted" playsinline="playsinline"></video></figure><div class="wp-block-media-text__content"></div></div><!-- /wp:media-text -->');
+      expect(wp.validateBlock(blocks[0])[0]).toBe(false);
+    } finally {
+      error.mockRestore();
+      warn.mockRestore();
+    }
+  });
+
+  it.each([true, false])('validates the public transformer output (controls=%s)', (controls) => {
+    const markup = execFileSync('php', ['-r', `
+      require 'vendor/autoload.php';
+      $html = file_get_contents('tests/fixtures/text-video-grid.html');
+      if (${controls ? 'false' : 'true'}) $html = str_replace(' controls', '', $html);
+      echo (new Automattic\\BlocksEngine\\PhpTransformer\\HtmlToBlocks\\HtmlTransformer())->transform($html)->toArray()['serialized_blocks'];
+    `], { cwd: transformer, encoding: 'utf8' });
+    const flatten = (blocks: Block[]): Block[] => blocks.flatMap((block) => [block, ...flatten(block.innerBlocks)]);
+    const blocks = flatten(wp.parse(markup));
+    expect(blocks.map((block) => wp.validateBlock(block)[0])).toEqual(blocks.map(() => true));
+    expect(blocks.some((block) => block.name === 'core/media-text')).toBe(false);
+    const video = blocks.find((block) => block.name === 'core/video');
+    expect(video?.attributes).toMatchObject({ src: 'clip.mp4', poster: 'poster.jpg', preload: 'metadata', controls, loop: true, muted: true, playsInline: true });
+  });
+});
diff --git a/php-transformer/composer.json b/php-transformer/composer.json
index af3efab57..6ddd21300 100644
--- a/php-transformer/composer.json
+++ b/php-transformer/composer.json
@@ -477,6 +477,7 @@
       "php tests/unit/embed-author-height-overrides-attribute.php",
       "php tests/unit/media-text-block-factory.php",
       "php tests/unit/video-element-conversion.php",
+      "php tests/unit/text-video-grid.php",
       "php tests/contract/native-video-poster.php",
       "php tests/contract/native-progress-meter.php",
       "php tests/contract/small-fixed-size-image-beside-text.php",
diff --git a/php-transformer/src/HtmlToBlocks/BlockFactory.php b/php-transformer/src/HtmlToBlocks/BlockFactory.php
index b8df1fc9e..b70455c23 100644
--- a/php-transformer/src/HtmlToBlocks/BlockFactory.php
+++ b/php-transformer/src/HtmlToBlocks/BlockFactory.php
@@ -227,23 +227,6 @@ private function commentAttrs(string $name, array $attrs): array
             // core's save() never reads it back, so it never belongs in the
             // serialized comment.
             unset($attrs['mediaFigureClassName']);
-            // Internal-only: consumed by mediaTextVideoAttrs() to build the
-            // video pane's <video> tag (dimensions, poster, native playback
-            // state). core/media-text's save() has no attribute for any of
-            // these — it renders a fixed `<video controls src={mediaUrl} />`
-            // — so none of them belong in the serialized comment.
-            foreach ( array(
-                'mediaVideoWidth',
-                'mediaVideoHeight',
-                'mediaVideoPoster',
-                'mediaVideoPreload',
-                'mediaVideoAutoplay',
-                'mediaVideoLoop',
-                'mediaVideoMuted',
-                'mediaVideoPlaysInline',
-            ) as $internalKey ) {
-                unset($attrs[ $internalKey ]);
-            }
             if ( '' === ($attrs['mediaAlt'] ?? null) ) {
                 unset($attrs['mediaAlt']);
             }
@@ -666,7 +649,7 @@ private function mediaTextMediaHtml(array $attrs): string
     {
         $mediaUrl = (string) ($attrs['mediaUrl'] ?? '');
         if ( 'video' === ($attrs['mediaType'] ?? '') ) {
-            return '<video controls' . $this->htmlAttrs($this->mediaTextVideoAttrs($attrs, $mediaUrl)) . '></video>';
+            return '<video controls' . $this->htmlAttrs(array('src' => $mediaUrl)) . '></video>';
         }
 
         if ( 'image' !== ($attrs['mediaType'] ?? '') ) {
@@ -694,38 +677,6 @@ private function mediaTextMediaHtml(array $attrs): string
         )) . '>' . $image . '</a>';
     }
 
-    /**
-     * core/media-text's save() has no block attribute for a video pane's
-     * intrinsic dimensions, poster, or native playback state — see the
-     * `mediaVideo*` capture in `MediaTextPattern::match()`. Project those
-     * internal-only facts onto the pane's `<video>` tag here.
-     *
-     * @param array<string, mixed> $attrs
-     * @return array<string, string>
-     */
-    private function mediaTextVideoAttrs(array $attrs, string $mediaUrl): array
-    {
-        $videoAttrs = array(
-            'src'     => $mediaUrl,
-            'poster'  => (string) ($attrs['mediaVideoPoster'] ?? ''),
-            'preload' => (string) ($attrs['mediaVideoPreload'] ?? ''),
-            'width'   => (string) ($attrs['mediaVideoWidth'] ?? ''),
-            'height'  => (string) ($attrs['mediaVideoHeight'] ?? ''),
-        );
-        foreach ( array(
-            'mediaVideoAutoplay'    => 'autoplay',
-            'mediaVideoLoop'        => 'loop',
-            'mediaVideoMuted'       => 'muted',
-            'mediaVideoPlaysInline' => 'playsinline',
-        ) as $attributeName => $htmlName ) {
-            if ( ! empty($attrs[ $attributeName ]) ) {
-                $videoAttrs[ $htmlName ] = $htmlName;
-            }
-        }
-
-        return $videoAttrs;
-    }
-
     /**
      * Resolve the wrapper tag for a `core/group`. Core's group `save()` renders
      * `<TagName>` from the `tagName` attribute, defaulting to `div`. Only the
@@ -990,7 +941,8 @@ private function mediaHtml(string $tagName, array $attrs): string
         $mediaAttrs = array(
             'src'      => (string) ($attrs['src'] ?? ''),
             'poster'   => (string) ($attrs['poster'] ?? ''),
-            'preload'  => (string) ($attrs['preload'] ?? ''),
+            // Core video omits its default preload value from save markup.
+            'preload'  => 'video' === $tagName && 'metadata' === ($attrs['preload'] ?? '') ? '' : (string) ($attrs['preload'] ?? ''),
             'width'    => (string) ($attrs['width'] ?? ''),
             'height'   => (string) ($attrs['height'] ?? ''),
             'controls' => ! empty($attrs['controls']) ? 'controls' : '',
diff --git a/php-transformer/src/HtmlToBlocks/Patterns/MediaTextPattern.php b/php-transformer/src/HtmlToBlocks/Patterns/MediaTextPattern.php
index ada9049e0..2a84f31eb 100644
--- a/php-transformer/src/HtmlToBlocks/Patterns/MediaTextPattern.php
+++ b/php-transformer/src/HtmlToBlocks/Patterns/MediaTextPattern.php
@@ -16,7 +16,7 @@
  *
  * exactly two element children? -------- no --> null
  * |
- * +-- exactly one pure img/video side? -- no --> null
+ * +-- exactly one pure image side? ------ no --> null
  * |
  * +-- text side out of flow (overlay)? -- yes -> null
  * |
@@ -124,7 +124,10 @@ public function match(
         if ( 'img' === $mediaType && (new SourceElementClassifier())->hasResponsiveImageSources($resolution['media']) ) {
             return null;
         }
-        if ( 'video' === $mediaType && $resolution['anchor'] instanceof DOMElement ) {
+        // core/media-text cannot retain native video playback attributes or
+        // the source pane layout. Keep videos editable through core/video
+        // inside the ordinary source group layout instead.
+        if ( 'video' === $mediaType ) {
             return null;
         }
 
@@ -316,52 +319,9 @@ public function match(
         }
         unset($attrs['layout']);
 
-        $attrs['mediaType'] = 'img' === $mediaType ? 'image' : 'video';
+        $attrs['mediaType'] = 'image';
         $attrs['mediaUrl']  = $mediaUrl;
 
-        // core/media-text's save() renders a video pane as a fixed
-        // `<video controls src={mediaUrl} />` — no attribute exists for
-        // intrinsic dimensions, poster, or native playback state. Without
-        // width/height the video collapses to the browser's 300x150 default
-        // intrinsic size before it can load, shifting every section below
-        // it. These facts still have to reach the saved `<video>` markup
-        // without becoming part of the serialized comment (core's save()
-        // never reads them back), so they use the same internal-only carrier
-        // shape as `mediaFigureClassName`: BlockFactory consumes the
-        // `mediaVideo*` keys to build the pane's `<video>` tag and strips
-        // them from the comment attrs before serialization.
-        if ( 'video' === $mediaType ) {
-            $videoAttrs = array_filter(array(
-                'mediaVideoWidth'   => trim($this->attr($resolution['media'], 'width')),
-                'mediaVideoHeight'  => trim($this->attr($resolution['media'], 'height')),
-                'mediaVideoPreload' => trim($this->attr($resolution['media'], 'preload')),
-            ), static fn (string $value): bool => '' !== $value);
-            $attrs = array_merge($attrs, $videoAttrs);
-
-            $poster = trim($this->attr($resolution['media'], 'poster'));
-            if ( '' !== $poster ) {
-                try {
-                    $posterUrl = $this->safeMediaUrl(trim($resolveAssetUrl($poster)));
-                } catch ( \Throwable ) {
-                    $posterUrl = '';
-                }
-                if ( '' !== $posterUrl ) {
-                    $attrs['mediaVideoPoster'] = $posterUrl;
-                }
-            }
-
-            foreach ( array(
-                'autoplay'    => 'mediaVideoAutoplay',
-                'loop'        => 'mediaVideoLoop',
-                'muted'       => 'mediaVideoMuted',
-                'playsinline' => 'mediaVideoPlaysInline',
-            ) as $sourceAttribute => $attributeName ) {
-                if ( $resolution['media']->hasAttribute($sourceAttribute) ) {
-                    $attrs[ $attributeName ] = true;
-                }
-            }
-        }
-
         // core/media-text's save() puts `className` on the outer wrapper
         // `<div>` only — never on the generated `<figure
         // class="wp-block-media-text__media">` pane. When the matched
diff --git a/php-transformer/src/HtmlToBlocks/Style/EngineSupportCss.php b/php-transformer/src/HtmlToBlocks/Style/EngineSupportCss.php
index d58490d4e..86b94347e 100644
--- a/php-transformer/src/HtmlToBlocks/Style/EngineSupportCss.php
+++ b/php-transformer/src/HtmlToBlocks/Style/EngineSupportCss.php
@@ -149,6 +149,11 @@ public function beforeAuthorCss(string $serializedBlocks): array
             $parts[] = $emptyParagraph . '{line-height:0}'
                 . $emptyParagraph . '>[data-rich-text-placeholder]{display:none}';
         }
+        if ( str_contains($serializedBlocks, SourceBlockAttributeProjector::SYNTHETIC_FILL_VIDEO_FIGURE_CLASS) ) {
+            // The injected figure must pass the source's percentage height
+            // through to its original containing block, not create an auto box.
+            $parts[] = ':root :where(figure.' . SourceBlockAttributeProjector::SYNTHETIC_FILL_VIDEO_FIGURE_CLASS . '){width:100%;height:100%;margin:0}';
+        }
         if ( str_contains($serializedBlocks, '<video') ) {
             $parts[] = 'video{max-width:100%}';
         }
diff --git a/php-transformer/src/HtmlToBlocks/Style/SourceBlockAttributeProjector.php b/php-transformer/src/HtmlToBlocks/Style/SourceBlockAttributeProjector.php
index 667e7a1a7..94019fd7f 100644
--- a/php-transformer/src/HtmlToBlocks/Style/SourceBlockAttributeProjector.php
+++ b/php-transformer/src/HtmlToBlocks/Style/SourceBlockAttributeProjector.php
@@ -25,6 +25,7 @@ final class SourceBlockAttributeProjector
     public const SYNTHETIC_INLINE_IMAGE_FIGURE_CLASS = 'blocks-engine-synthetic-image-figure-inline';
     public const SYNTHETIC_IMAGE_GAP_CLASS = 'blocks-engine-synthetic-image-gap';
     public const SYNTHETIC_FILL_IMAGE_FIGURE_CLASS = 'blocks-engine-synthetic-image-figure-fill';
+    public const SYNTHETIC_FILL_VIDEO_FIGURE_CLASS = 'blocks-engine-synthetic-video-figure-fill';
     public const SYNTHETIC_EMBED_FIGURE_CLASS = 'blocks-engine-synthetic-embed-figure';
     public const CSS_OWNED_INLINE_FLOW_CLASS = 'blocks-engine-css-owned-inline-flow';
     public const CSS_OWNED_LAYOUT_ITEM_CLASS = 'blocks-engine-css-owned-layout-item';
@@ -57,6 +58,7 @@ final class SourceBlockAttributeProjector
             self::PROPAGATED_LINK_CLASS,
             self::PROPAGATED_LINK_COLOR_CLASS,
         ),
+        'core/video'     => array(self::SYNTHETIC_FILL_VIDEO_FIGURE_CLASS),
         'core/image'     => array(
             self::SYNTHETIC_IMAGE_FIGURE_CLASS,
             self::SYNTHETIC_FLEX_IMAGE_FIGURE_CLASS,
@@ -117,6 +119,13 @@ public function project(
                 $attrs['className'] = SourceDom::mergeClassNames((string) ($attrs['className'] ?? ''), self::SYNTHETIC_FILL_IMAGE_FIGURE_CLASS);
             }
         }
+        if ( 'core/video' === $name && 'video' === $sourceTagName ) {
+            $declarations = $this->styleResolver->resolvedPresentationDeclarations($sourceElement);
+            if ( '100%' === CssValueInspector::comparable((string) ($declarations['width'] ?? ''))
+                && '100%' === CssValueInspector::comparable((string) ($declarations['height'] ?? '')) ) {
+                $attrs['className'] = SourceDom::mergeClassNames((string) ($attrs['className'] ?? ''), self::SYNTHETIC_FILL_VIDEO_FIGURE_CLASS);
+            }
+        }
         if ( 'core/paragraph' === $name && $facts->isInlineSourceElement ) {
             $attrs['className'] = SourceDom::mergeClassNames((string) ($attrs['className'] ?? ''), self::SYNTHETIC_PARAGRAPH_CLASS);
             if ( 'a' === $sourceTagName && $this->sourceAnchorHasNoTextDecoration($sourceElement) ) {
diff --git a/php-transformer/src/WordPressSitePlan/WordPressSitePlanResolver.php b/php-transformer/src/WordPressSitePlan/WordPressSitePlanResolver.php
index bded7ab2d..d63a83eb1 100644
--- a/php-transformer/src/WordPressSitePlan/WordPressSitePlanResolver.php
+++ b/php-transformer/src/WordPressSitePlan/WordPressSitePlanResolver.php
@@ -82,12 +82,13 @@ public static function resolveMarkup(string $markup, array $references, array $a
             foreach ($blocks as &$block) {
                 $attrs = &$block['attrs'];
                 $name = $block['blockName'];
-                $field = 'core/media-text' === $name ? 'mediaUrl' : 'url';
+                $field = 'core/media-text' === $name ? 'mediaUrl' : ('core/video' === $name ? 'src' : 'url');
                 $url = $attrs[$field] ?? '';
                 if ('core/image' === $name && preg_match('/<img\b[^>]*\bsrc=["\']([^"\']*)["\']/i', $block['innerHTML'], $match)) $url = html_entity_decode($match[1], ENT_QUOTES | ENT_HTML5);
+                if ('core/video' === $name && preg_match('/<video\b[^>]*\bsrc=["\']([^"\']*)["\']/i', $block['innerHTML'], $match)) $url = html_entity_decode($match[1], ENT_QUOTES | ENT_HTML5);
                 foreach ($attachments as $token => $attachment) {
                     $canonical = WordPressSitePlan::TOKEN_PREFIX . $token . '}}';
-                    if ($url === $canonical && in_array($name, array('core/image', 'core/cover', 'core/media-text'), true)) {
+                    if ($url === $canonical && in_array($name, array('core/image', 'core/cover', 'core/media-text', 'core/video'), true)) {
                         $attrs['core/media-text' === $name ? 'mediaId' : 'id'] = $attachment['id'];
                         $attrs[$field] = $canonical;
                         if ('core/image' === $name) {
diff --git a/php-transformer/tests/fixtures/parity/html-media-text.json b/php-transformer/tests/fixtures/parity/html-media-text.json
index af22e74eb..31e291b22 100644
--- a/php-transformer/tests/fixtures/parity/html-media-text.json
+++ b/php-transformer/tests/fixtures/parity/html-media-text.json
@@ -1,11 +1,11 @@
 {
   "schema": "blocks-engine/php-transformer/parity-fixture/v1",
   "name": "html-media-text",
-  "description": "Converts video/text layouts to native core/media-text while preserving responsive picture image/text layouts through a generated companion block.",
+  "description": "Keeps video/text layouts in native groups with editable core/video while preserving responsive picture image/text layouts through a generated companion block.",
   "source_reference": {
     "repo": "php-transformer",
     "path": "tests/fixtures/parity/html-media-text.json",
-    "notes": "Covers a linked picture-backed image on the left and a video on the right; responsive source selection remains intact through a generated block while the representable video layout remains native."
+    "notes": "Covers a linked picture-backed image on the left and a video on the right; responsive source selection remains intact through a generated block while the video retains its source layout."
   },
   "legacy_comparison": {
     "skip": true,
@@ -20,9 +20,10 @@
     { "path": "blocks.0.innerBlocks.0", "name": "custom/responsive-media" },
     { "path": "blocks.0.innerBlocks.1.innerBlocks.0", "name": "core/heading", "attrs": { "content": "Image feature", "level": 2 } },
     { "path": "blocks.0.innerBlocks.1.innerBlocks.1", "name": "core/paragraph", "attrs": { "content": "Linked media stays beside readable copy." } },
-    { "path": "blocks.1", "name": "core/media-text", "attrs": { "className": "video-split", "mediaPosition": "right", "mediaType": "video", "mediaUrl": "https://example.com/feature.mp4", "mediaWidth": 35, "verticalAlignment": "center" } },
-    { "path": "blocks.1.innerBlocks.0", "name": "core/heading", "attrs": { "content": "Video feature", "level": 3 } },
-    { "path": "blocks.1.innerBlocks.1", "name": "core/paragraph", "attrs": { "content": "Video renders on the right." } }
+    { "path": "blocks.1", "name": "core/group" },
+    { "path": "blocks.1.innerBlocks.0.innerBlocks.0", "name": "core/heading", "attrs": { "content": "Video feature", "level": 3 } },
+    { "path": "blocks.1.innerBlocks.0.innerBlocks.1", "name": "core/paragraph", "attrs": { "content": "Video renders on the right." } },
+    { "path": "blocks.1.innerBlocks.1", "name": "core/video", "attrs": { "src": "https://example.com/feature.mp4", "controls": false } }
   ],
   "expected_fallbacks": [],
   "expect": [
@@ -34,6 +35,6 @@
     { "path": "source_reports.conversion_report.metrics.fallback_count", "assert": "equals", "value": 0 },
     { "path": "coverage.0.fallback_count", "assert": "equals", "value": 0 },
     { "path": "serialized_blocks", "assert": "contains", "value": "https://example.com/feature.webp" },
-    { "path": "serialized_blocks", "assert": "contains", "value": "<!-- wp:media-text" }
+    { "path": "serialized_blocks", "assert": "contains", "value": "<!-- wp:video" }
   ]
 }
diff --git a/php-transformer/tests/fixtures/text-video-grid.html b/php-transformer/tests/fixtures/text-video-grid.html
new file mode 100644
index 000000000..0d468d36c
--- /dev/null
+++ b/php-transformer/tests/fixtures/text-video-grid.html
@@ -0,0 +1,9 @@
+<!doctype html><html><head><title>Split</title><style>
+body{margin:0}.wrap{max-width:1180px;margin:0 auto;padding-inline:20px}
+.split .wrap{display:grid;grid-template-columns:1fr 1.25fr;gap:44px;align-items:center}
+.split .frame{aspect-ratio:16/9;background:#000}.split video{width:100%;height:100%;object-fit:cover;display:block}
+@media (max-width:860px){.split .wrap{grid-template-columns:1fr;gap:28px}}
+</style></head><body><main><section class="split"><div class="wrap">
+<div class="head"><h2>Watch the build</h2><p>From raw steel to a finished structure, this is the kind of building we design.</p></div>
+<div class="frame"><video src="clip.mp4" poster="poster.jpg" controls muted loop playsinline preload="metadata"></video></div>
+</div></section></main></body></html>
diff --git a/php-transformer/tests/unit/media-text-block-factory.php b/php-transformer/tests/unit/media-text-block-factory.php
index c8cd2be09..7fe04f9a4 100644
--- a/php-transformer/tests/unit/media-text-block-factory.php
+++ b/php-transformer/tests/unit/media-text-block-factory.php
@@ -142,38 +142,6 @@
 $assertNotContains('is-stacked-on-mobile', $video['innerHTML'], 'Explicit false omits stacked class.');
 $assertNotContains('<a', $video['innerHTML'], 'Video does not use image-only link attributes.');
 
-// core/media-text has no block attribute for a video pane's intrinsic
-// dimensions, poster, or native playback state — its save() renders a fixed
-// `<video controls src={mediaUrl} />`. MediaTextPattern still captures those
-// facts under internal-only `mediaVideo*` keys (dropping them collapses the
-// video to the browser's 300x150 default intrinsic size before it can load,
-// shifting every section below it); BlockFactory projects them onto the
-// saved `<video>` tag here and strips the carrier keys from the comment.
-$sizedVideo = $factory->create('core/media-text', array(
-    'mediaType'             => 'video',
-    'mediaUrl'              => 'https://example.com/clip.mp4',
-    'mediaVideoWidth'       => '1280',
-    'mediaVideoHeight'      => '720',
-    'mediaVideoPoster'      => 'https://example.com/clip.jpg',
-    'mediaVideoPreload'     => 'none',
-    'mediaVideoAutoplay'    => true,
-    'mediaVideoLoop'        => true,
-    'mediaVideoMuted'       => true,
-    'mediaVideoPlaysInline' => true,
-), array());
-$assertContains(
-    '<figure class="wp-block-media-text__media"><video controls src="https://example.com/clip.mp4" poster="https://example.com/clip.jpg" preload="none" width="1280" height="720" autoplay="autoplay" loop="loop" muted="muted" playsinline="playsinline"></video></figure>',
-    $sizedVideo['innerHTML'],
-    'Video pane emits dimensions, poster, and native playback attributes onto the saved <video> tag.'
-);
-foreach ( array( 'mediaVideoWidth', 'mediaVideoHeight', 'mediaVideoPoster', 'mediaVideoPreload', 'mediaVideoAutoplay', 'mediaVideoLoop', 'mediaVideoMuted', 'mediaVideoPlaysInline' ) as $internalKey ) {
-    $assertSame(false, array_key_exists($internalKey, $sizedVideo['attrs'] ?? array()), $internalKey . ' never reaches the serialized block comment attrs.');
-}
-$sizedVideoValidity = ( new Runtime() )->validateBlockSerialization(array( $sizedVideo ));
-$assertSame('pass', $sizedVideoValidity['status'] ?? null, 'Video dimension/poster/playback carrier attrs do not trip serialization validators.');
-$sizedVideoFindings = ( new CanonicalSaveShapeValidator() )->findings(array( $sizedVideo ));
-$assertSame(array(), $sizedVideoFindings, 'Video dimension/poster/playback carrier attrs do not trip the canonical save-shape validator.');
-
 // A source `<figure>` that wraps the media pane has nowhere else to put its
 // classes: core/media-text's save() only reads `className` onto the outer
 // wrapper `<div>`, never onto the generated `<figure
diff --git a/php-transformer/tests/unit/media-text-pattern.php b/php-transformer/tests/unit/media-text-pattern.php
index ea2c31c23..93e513c55 100644
--- a/php-transformer/tests/unit/media-text-pattern.php
+++ b/php-transformer/tests/unit/media-text-pattern.php
@@ -374,39 +374,23 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 $record = array();
 $videoElement = $elementFromHtml('<section style="display:flex"><div><video src="clip.mp4" controls></video></div><div><p>Watch</p></div></section>');
 $video = $match($videoElement, array( $paragraph ), $fallbacks, $record);
-$assertSame('video', $video['attrs']['mediaType'] ?? null, 'Video media emits mediaType video.');
-$assertSame('/resolved/clip.mp4', $video['attrs']['mediaUrl'] ?? null, 'Video src passes through asset resolver.');
-$assertTrue(! array_key_exists('mediaAlt', $video['attrs'] ?? array()), 'Video media omits mediaAlt.');
-
-// core/media-text has no attribute for a video pane's intrinsic dimensions,
-// poster, or native playback state — dropping them collapses the video to
-// the browser's 300x150 default before it can load, shifting every section
-// below it. The pattern still captures them, under internal-only
-// `mediaVideo*` keys BlockFactory consumes and strips before serialization.
+$assertNull($video, 'Video panes stay in native source layout with core/video.');
+
+// Native video attributes cannot round-trip through media-text save().
 $fallbacks = array();
 $record = array();
 $sizedVideoElement = $elementFromHtml(
     '<section style="display:flex"><div><video src="clip.mp4" poster="clip.jpg" playsinline preload="none" width="1280" height="720" autoplay loop muted></video></div><div><p>Watch</p></div></section>'
 );
 $sizedVideo = $match($sizedVideoElement, array( $paragraph ), $fallbacks, $record);
-$assertSame('1280', $sizedVideo['attrs']['mediaVideoWidth'] ?? null, 'Video width survives as an internal-only carrier attr.');
-$assertSame('720', $sizedVideo['attrs']['mediaVideoHeight'] ?? null, 'Video height survives as an internal-only carrier attr.');
-$assertSame('/resolved/clip.jpg', $sizedVideo['attrs']['mediaVideoPoster'] ?? null, 'Video poster resolves through the asset resolver and survives as an internal-only carrier attr.');
-$assertSame('none', $sizedVideo['attrs']['mediaVideoPreload'] ?? null, 'Video preload survives as an internal-only carrier attr.');
-$assertSame(true, $sizedVideo['attrs']['mediaVideoAutoplay'] ?? null, 'Video autoplay survives as an internal-only carrier attr.');
-$assertSame(true, $sizedVideo['attrs']['mediaVideoLoop'] ?? null, 'Video loop survives as an internal-only carrier attr.');
-$assertSame(true, $sizedVideo['attrs']['mediaVideoMuted'] ?? null, 'Video muted survives as an internal-only carrier attr.');
-$assertSame(true, $sizedVideo['attrs']['mediaVideoPlaysInline'] ?? null, 'Video playsinline survives as an internal-only carrier attr.');
-
-// A video with no dimensions/poster/playback attrs still converts cleanly:
-// no carrier keys are fabricated.
+$assertNull($sizedVideo, 'Configured video panes decline media-text promotion.');
+
+// Even a plain video keeps source layout rather than media-text defaults.
 $fallbacks = array();
 $record = array();
 $plainVideoElement = $elementFromHtml('<section style="display:flex"><div><video src="plain.mp4"></video></div><div><p>Watch</p></div></section>');
 $plainVideo = $match($plainVideoElement, array( $paragraph ), $fallbacks, $record);
-foreach ( array( 'mediaVideoWidth', 'mediaVideoHeight', 'mediaVideoPoster', 'mediaVideoPreload', 'mediaVideoAutoplay', 'mediaVideoLoop', 'mediaVideoMuted', 'mediaVideoPlaysInline' ) as $internalKey ) {
-    $assertTrue(! array_key_exists($internalKey, $plainVideo['attrs'] ?? array()), 'A dimensionless/posterless video fabricates no ' . $internalKey . ' carrier attr.');
-}
+$assertNull($plainVideo, 'Plain video panes decline media-text promotion.');
 
 // Link wrapper attributes survive.
 $fallbacks = array();
@@ -1150,19 +1134,19 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 $fallbacks = array();
 $record = array();
 $figureWrappedElement = $elementByClass(
-    '<figure class="in"><div class="frame"><div class="vid" style="display:flex"><video src="clip.mp4"></video><button class="play" type="button">Play</button></div></div></figure>',
+    '<figure class="in"><div class="frame"><div class="vid" style="display:flex"><img src="photo.jpg"><button class="play" type="button">Play</button></div></div></figure>',
     'div',
     'vid'
 );
 $figureWrapped = $match($figureWrappedElement, array( $paragraph ), $fallbacks, $record);
-$assertSame('core/media-text', $figureWrapped['blockName'] ?? null, 'Figure-wrapped video pane still matches core/media-text.');
+$assertSame('core/media-text', $figureWrapped['blockName'] ?? null, 'Figure-wrapped image pane still matches core/media-text.');
 $assertSame('in', $figureWrapped['attrs']['mediaFigureClassName'] ?? null, 'Enclosing source figure class reaches mediaFigureClassName.');
 $assertTrue(! array_key_exists('className', $figureWrapped['attrs'] ?? array()), 'Enclosing source figure class does not leak onto the wrapper className.');
 
 $fallbacks = array();
 $record = array();
 $noFigureElement = $elementByClass(
-    '<div class="shell"><div class="vid" style="display:flex"><video src="clip.mp4"></video><button class="play" type="button">Play</button></div></div>',
+    '<div class="shell"><div class="vid" style="display:flex"><img src="photo.jpg"><button class="play" type="button">Play</button></div></div>',
     'div',
     'vid'
 );
@@ -1172,7 +1156,7 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 $fallbacks = array();
 $record = array();
 $unclassedFigureElement = $elementByClass(
-    '<figure><div class="frame"><div class="vid" style="display:flex"><video src="clip.mp4"></video><button class="play" type="button">Play</button></div></div></figure>',
+    '<figure><div class="frame"><div class="vid" style="display:flex"><img src="photo.jpg"><button class="play" type="button">Play</button></div></div></figure>',
     'div',
     'vid'
 );
@@ -1185,14 +1169,14 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 $fallbacks = array();
 $record = array();
 $sharedFigureElement = $elementByClass(
-    '<figure class="in"><div class="frame"><div class="vid" style="display:flex"><video src="clip.mp4"></video><button class="play" type="button">Play</button></div></div><figcaption>Shared caption</figcaption></figure>',
+    '<figure class="in"><div class="frame"><div class="vid" style="display:flex"><img src="photo.jpg"><button class="play" type="button">Play</button></div></div><figcaption>Shared caption</figcaption></figure>',
     'div',
     'vid'
 );
 $sharedFigure = $match($sharedFigureElement, array( $paragraph ), $fallbacks, $record);
 $assertTrue(! array_key_exists('mediaFigureClassName', $sharedFigure['attrs'] ?? array()), 'A figure with a non-wrapper sibling emits no mediaFigureClassName.');
 
-// End-to-end invariant: a source `<figure class="X">` wrapping a video tile
+// End-to-end invariant: a source `<figure class="X">` wrapping an image tile
 // must still be matched by a literal `figure.X` author selector once
 // converted — the exact rule shape a scroll-reveal script depends on
 // (`figure { opacity: 0 } figure.X { opacity: 1 }`). Losing this either
@@ -1239,7 +1223,7 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 // A single "frame" wrapper between the source figure and the matched
 // media/text container — the exact shape #2087 fixed and #2101 regressed.
 $revealResult = $transformHtml(
-    '<figure class="in"><div class="frame"><div class="vid" style="display:flex"><video src="clip.mp4"></video><button class="play" type="button">Play</button></div></div></figure>'
+    '<figure class="in"><div class="frame"><div class="vid" style="display:flex"><img src="photo.jpg"><button class="play" type="button">Play</button></div></div></figure>'
 );
 $revealMediaTextBlock = $collectMediaText($revealResult['blocks'] ?? array());
 $assertTrue(is_array($revealMediaTextBlock), 'Reveal fixture converts to a core/media-text block somewhere in the tree.');
@@ -1261,7 +1245,7 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 // container: an even deeper chain than what regressed #2087, proving the
 // carrier does not depend on a specific wrapper count.
 $deeplyWrappedResult = $transformHtml(
-    '<figure class="in"><div class="frame"><div class="inner"><div class="vid" style="display:flex"><video src="clip.mp4"></video><button class="play" type="button">Play</button></div></div></div></figure>'
+    '<figure class="in"><div class="frame"><div class="inner"><div class="vid" style="display:flex"><img src="photo.jpg"><button class="play" type="button">Play</button></div></div></div></figure>'
 );
 $deeplyWrappedMediaTextBlock = $collectMediaText($deeplyWrappedResult['blocks'] ?? array());
 $assertTrue(is_array($deeplyWrappedMediaTextBlock), 'Deeply wrapped reveal fixture converts to a core/media-text block somewhere in the tree.');
@@ -1284,38 +1268,6 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
     'A literal figure.in author selector matches the emitted core/image markup too.'
 );
 
-// End-to-end: a video's intrinsic dimensions, poster, and native playback
-// attributes reach the saved media-text markup without ever entering the
-// serialized block comment, and the block still passes both validity
-// validators.
-$sizedVideoResult = $transformHtml(
-    '<section style="display:flex"><div><video src="https://example.com/clip.mp4" poster="https://example.com/clip.jpg" playsinline preload="none" width="1280" height="720" autoplay loop muted></video></div><div><p>Watch</p></div></section>'
-);
-$sizedVideoBlock = $sizedVideoResult['blocks'][0] ?? array();
-$assertSame('core/media-text', $sizedVideoBlock['blockName'] ?? null, 'Sized video fixture converts to core/media-text.');
-$assertContains(
-    '<video controls src="https://example.com/clip.mp4" poster="https://example.com/clip.jpg" preload="none" width="1280" height="720" autoplay="autoplay" loop="loop" muted="muted" playsinline="playsinline"></video>',
-    (string) ($sizedVideoBlock['innerHTML'] ?? ''),
-    'Dimensions, poster, and native playback attributes all reach the saved <video> markup.'
-);
-foreach ( array( 'mediaVideoWidth', 'mediaVideoHeight', 'mediaVideoPoster', 'mediaVideoPreload', 'mediaVideoAutoplay', 'mediaVideoLoop', 'mediaVideoMuted', 'mediaVideoPlaysInline' ) as $internalKey ) {
-    $assertTrue(! array_key_exists($internalKey, $sizedVideoBlock['attrs'] ?? array()), $internalKey . ' never reaches the serialized block comment attrs.');
-}
-$sizedVideoValidity = ( new Runtime() )->validateBlockSerialization($sizedVideoResult['blocks']);
-$assertSame('pass', $sizedVideoValidity['status'] ?? null, 'Video dimension/poster/playback carrier attrs do not trip serialization validators.');
-$sizedVideoFindings = ( new \Automattic\BlocksEngine\PhpTransformer\WordPress\CanonicalSaveShapeValidator() )->findings($sizedVideoResult['blocks']);
-$assertSame(array(), $sizedVideoFindings, 'Video dimension/poster/playback carrier attrs do not trip the canonical save-shape validator.');
-
-// Regression: a video with no dimensions/poster/playback attrs still
-// converts to the same plain markup as before this fix.
-$plainVideoResult = $transformHtml('<section style="display:flex"><div><video src="https://example.com/plain.mp4"></video></div><div><p>Watch</p></div></section>');
-$plainVideoBlock = $plainVideoResult['blocks'][0] ?? array();
-$assertContains(
-    '<figure class="wp-block-media-text__media"><video controls src="https://example.com/plain.mp4"></video></figure>',
-    (string) ($plainVideoBlock['innerHTML'] ?? ''),
-    'A dimensionless/posterless video keeps emitting the original plain <video controls src> markup.'
-);
-
 // An absolutely-positioned control removed from flow can never be a real
 // flex/grid item, so it can never be the container's second pane — the
 // unit-level gate declines before text conversion, independent of what the
@@ -1367,7 +1319,7 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 foreach ( array( '', 'position:relative', 'position:sticky;top:0', 'position:static' ) as $inFlowPosition ) {
     $fallbacks = array();
     $record = array();
-    $inFlowElement = $elementFromHtml('<section style="display:flex"><video src="clip.mp4"></video><div><p>Watch</p></div></section>');
+    $inFlowElement = $elementFromHtml('<section style="display:flex"><img src="photo.jpg"><div><p>Watch</p></div></section>');
     $inFlowBlock = $match(
         $inFlowElement,
         array( $paragraph ),
@@ -1480,7 +1432,7 @@ static function (string $name, array $attrs, array $innerBlocks, ?DOMElement $so
 $genuineTwoPaneResult = $transformHtml(
     '<style>.frame{display:flex;justify-content:center}.vid{display:flex;justify-content:center;max-width:100%}</style>'
     . '<figure class="in"><div class="frame"><div class="vid">'
-    . '<video src="clip.mp4" width="1280" height="720"></video>'
+    . '<img src="photo.jpg" width="1280" height="720">'
     . '<div><h2>About this clip</h2><p>Behind the scenes footage.</p></div>'
     . '</div></div></figure>'
 );
diff --git a/php-transformer/tests/unit/text-video-grid.php b/php-transformer/tests/unit/text-video-grid.php
new file mode 100644
index 000000000..1c06f9af1
--- /dev/null
+++ b/php-transformer/tests/unit/text-video-grid.php
@@ -0,0 +1,56 @@
+<?php
+declare(strict_types=1);
+
+require dirname(__DIR__, 2) . '/vendor/autoload.php';
+
+use Automattic\BlocksEngine\PhpTransformer\ArtifactCompiler\ArtifactCompiler;
+use Automattic\BlocksEngine\PhpTransformer\HtmlToBlocks\HtmlTransformer;
+use Automattic\BlocksEngine\PhpTransformer\WordPressSitePlan\WordPressSitePlanResolver;
+use Automattic\BlocksEngine\PhpTransformer\WordPress\Runtime;
+
+$assert = static function (bool $condition, string $message): void {
+    if (!$condition) throw new RuntimeException($message);
+};
+$html = file_get_contents(dirname(__DIR__) . '/fixtures/text-video-grid.html');
+$flatten = static function (array $blocks) use (&$flatten): array {
+    $out = array();
+    foreach ($blocks as $block) { $out[] = $block; array_push($out, ...$flatten($block['innerBlocks'] ?? array())); }
+    return $out;
+};
+foreach (array(true, false) as $controls) {
+    $source = $controls ? $html : str_replace(' controls', '', $html);
+    $result = (new HtmlTransformer())->transform($source)->toArray();
+    $blocks = $flatten($result['blocks']);
+    $names = array_column($blocks, 'blockName');
+    $assert(!in_array('core/media-text', $names, true), 'Video grids must not promote to media-text.');
+    $assert(array() === $result['fallbacks'], 'The grid needs no fallback.');
+    $video = current(array_filter($blocks, static fn(array $block): bool => 'core/video' === $block['blockName']));
+    foreach (array('poster' => 'poster.jpg', 'preload' => 'metadata', 'controls' => $controls, 'loop' => true, 'muted' => true, 'playsInline' => true) as $name => $value) {
+        $assert($value === ($video['attrs'][$name] ?? null), 'core/video retains ' . $name);
+    }
+    $markup = $result['serialized_blocks'];
+    $assert(strpos($markup, 'Watch the build') < strpos($markup, '<video'), 'Text precedes video at every viewport.');
+    $assert(str_contains($markup, 'blocks-engine-css-owned-grid'), 'The source grid stays a native group grid.');
+    $css = implode("\n", array_column($result['assets'], 'content'));
+    $assert(str_contains($css, 'grid-template-columns:1fr 1.25fr;gap:44px') && str_contains($css, '@media (max-width:860px){.split .wrap{grid-template-columns:1fr;gap:28px}}'), 'Desktop tracks and authored collapse breakpoint remain CSS-owned.');
+}
+$artifact = array('entrypoint' => 'index.html', 'files' => array(
+    'index.html' => $html,
+    'clip.mp4' => array('path' => 'clip.mp4', 'kind' => 'video', 'mime_type' => 'video/mp4', 'content_base64' => base64_encode('video')),
+    'poster.jpg' => array('path' => 'poster.jpg', 'kind' => 'image', 'mime_type' => 'image/jpeg', 'content_base64' => base64_encode('poster')),
+));
+$plan = (new ArtifactCompiler())->compile($artifact)->toWordPressSitePlanView()['wordpress_site_plan'];
+$attachments = array();
+foreach ($plan['assets'] as $asset) {
+    if (!in_array($asset['source_path'], array('clip.mp4', 'poster.jpg'), true)) continue;
+    $assert('media_library' === $asset['destination'], 'Video and poster are Media Library assets.');
+    $attachments[$asset['token']] = array('id' => count($attachments) + 41, 'url' => 'https://example.test/uploads/' . basename($asset['source_path']));
+}
+$assert(2 === count($attachments), 'Both media files are inventoried.');
+$resolved = (new WordPressSitePlanResolver())->resolve($plan, array('theme_uri' => 'https://example.test/theme', 'attachment_resolutions' => $attachments));
+$markup = $resolved['pages'][0]['resolved_block_markup'];
+$assert(str_contains($markup, 'https://example.test/uploads/clip.mp4') && str_contains($markup, 'https://example.test/uploads/poster.jpg'), 'Media Library URLs replace local video and poster references.');
+$resolvedBlocks = $flatten((new Runtime())->parseBlocks($markup));
+$video = current(array_filter($resolvedBlocks, static fn(array $block): bool => 'core/video' === $block['blockName']));
+$assert(41 === ($video['attrs']['id'] ?? null) && !str_contains($markup, '/theme/assets/'), 'The editable video binds its own attachment ID rather than theme assets.');
+echo "Text/video grid contract passed.\n";