Markdoc asset bleed, second try (#7185)

* Revert "revert: markdoc asset bleed (#7178)"

This reverts commit 57e65d247f67de61bcc3a585c2254feb61ed2e74.

* fix: missing result param on `renderUniqueStylesheet`

* test: bundled styles (fails!)

* fix: use `type: 'external'` for links

* fix: split Astro components from markdoc config

* test: style bleed (it fails...)

* chore: remove unused util

* fix: revert entry change

* Stop traversing the graph when you encounter a propagated asset

* chore: cleanup unused `entry` prop

* refactor: add isPropagatedAssetsMod check

* chore: remove unused import

* chore: changeset

* Normalize path using vite

* Update packages/integrations/markdoc/src/index.ts

Co-authored-by: Ben Holmes <hey@bholmes.dev>

---------

Co-authored-by: Matthew Phillips <matthew@skypack.dev>
Co-authored-by: bholmesdev <bholmesdev@gmail.com>
Co-authored-by: Matthew Phillips <matthew@matthewphillips.info>

28 files changed, 653 insertions, 131 deletions

diff --git a/.changeset/smart-moles-double.md b/.changeset/smart-moles-double.md
new file mode 100644
index 000000000..072626ea5
--- /dev/null
+++ b/.changeset/smart-moles-double.md
@@ -0,0 +1,7 @@
+---
+'astro': patch
+'@astrojs/markdoc': patch
+'@astrojs/mdx': patch
+---
+
+Bring back improved style and script handling across content collection files. This addresses bugs found in a previous release to `@astrojs/markdoc`.
diff --git a/examples/with-markdoc/src/content/config.ts b/examples/with-markdoc/src/content/config.ts
deleted file mode 100644
index 2eccab0a3..000000000
--- a/examples/with-markdoc/src/content/config.ts
+++ /dev/null
@@ -1,9 +0,0 @@
-import { defineCollection, z } from 'astro:content';
-
-const docs = defineCollection({
-	schema: z.object({
-		title: z.string(),
-	}),
-});
-
-export const collections = { docs };
diff --git a/packages/astro/src/@types/astro.ts b/packages/astro/src/@types/astro.ts
index c3372ec25..e1e71c501 100644
--- a/packages/astro/src/@types/astro.ts
+++ b/packages/astro/src/@types/astro.ts
@@ -1276,6 +1276,12 @@ export interface ContentEntryType {
 		}
 	): rollup.LoadResult | Promise<rollup.LoadResult>;
 	contentModuleTypes?: string;
+	/**
+	 * Handle asset propagation for rendered content to avoid bleed.
+	 * Ex. MDX content can import styles and scripts, so `handlePropagation` should be true.
+	 * @default true
+	 */
+	handlePropagation?: boolean;
 }
 
 type GetContentEntryInfoReturnType = {
diff --git a/packages/astro/src/content/consts.ts b/packages/astro/src/content/consts.ts
index bda154692..9bfb2e865 100644
--- a/packages/astro/src/content/consts.ts
+++ b/packages/astro/src/content/consts.ts
@@ -1,11 +1,18 @@
 export const PROPAGATED_ASSET_FLAG = 'astroPropagatedAssets';
+export const CONTENT_RENDER_FLAG = 'astroRenderContent';
 export const CONTENT_FLAG = 'astroContentCollectionEntry';
 export const DATA_FLAG = 'astroDataCollectionEntry';
-export const CONTENT_FLAGS = [CONTENT_FLAG, DATA_FLAG, PROPAGATED_ASSET_FLAG] as const;
 
 export const VIRTUAL_MODULE_ID = 'astro:content';
 export const LINKS_PLACEHOLDER = '@@ASTRO-LINKS@@';
 export const STYLES_PLACEHOLDER = '@@ASTRO-STYLES@@';
 export const SCRIPTS_PLACEHOLDER = '@@ASTRO-SCRIPTS@@';
 
+export const CONTENT_FLAGS = [
+	CONTENT_FLAG,
+	CONTENT_RENDER_FLAG,
+	DATA_FLAG,
+	PROPAGATED_ASSET_FLAG,
+] as const;
+
 export const CONTENT_TYPES_FILE = 'types.d.ts';
diff --git a/packages/astro/src/content/runtime.ts b/packages/astro/src/content/runtime.ts
index 9187c4fce..84e3162bf 100644
--- a/packages/astro/src/content/runtime.ts
+++ b/packages/astro/src/content/runtime.ts
@@ -269,63 +269,80 @@ async function render({
 
 	const baseMod = await renderEntryImport();
 	if (baseMod == null || typeof baseMod !== 'object') throw UnexpectedRenderError;
+	const { default: defaultMod } = baseMod;
 
-	const { collectedStyles, collectedLinks, collectedScripts, getMod } = baseMod;
-	if (typeof getMod !== 'function') throw UnexpectedRenderError;
-	const mod = await getMod();
-	if (mod == null || typeof mod !== 'object') throw UnexpectedRenderError;
+	if (isPropagatedAssetsModule(defaultMod)) {
+		const { collectedStyles, collectedLinks, collectedScripts, getMod } = defaultMod;
+		if (typeof getMod !== 'function') throw UnexpectedRenderError;
+		const propagationMod = await getMod();
+		if (propagationMod == null || typeof propagationMod !== 'object') throw UnexpectedRenderError;
 
-	const Content = createComponent({
-		factory(result, baseProps, slots) {
-			let styles = '',
-				links = '',
-				scripts = '';
-			if (Array.isArray(collectedStyles)) {
-				styles = collectedStyles
-					.map((style: any) => {
-						return renderUniqueStylesheet(result, {
-							type: 'inline',
-							content: style,
-						});
-					})
-					.join('');
-			}
-			if (Array.isArray(collectedLinks)) {
-				links = collectedLinks
-					.map((link: any) => {
-						return renderUniqueStylesheet(result, {
-							type: 'external',
-							src: prependForwardSlash(link),
-						});
-					})
-					.join('');
-			}
-			if (Array.isArray(collectedScripts)) {
-				scripts = collectedScripts.map((script: any) => renderScriptElement(script)).join('');
-			}
+		const Content = createComponent({
+			factory(result, baseProps, slots) {
+				let styles = '',
+					links = '',
+					scripts = '';
+				if (Array.isArray(collectedStyles)) {
+					styles = collectedStyles
+						.map((style: any) => {
+							return renderUniqueStylesheet(result, {
+								type: 'inline',
+								content: style,
+							});
+						})
+						.join('');
+				}
+				if (Array.isArray(collectedLinks)) {
+					links = collectedLinks
+						.map((link: any) => {
+							return renderUniqueStylesheet(result, {
+								type: 'external',
+								src: prependForwardSlash(link),
+							});
+						})
+						.join('');
+				}
+				if (Array.isArray(collectedScripts)) {
+					scripts = collectedScripts.map((script: any) => renderScriptElement(script)).join('');
+				}
 
-			let props = baseProps;
-			// Auto-apply MDX components export
-			if (id.endsWith('.mdx')) {
-				props = {
-					components: mod.components ?? {},
-					...baseProps,
-				};
-			}
+				let props = baseProps;
+				// Auto-apply MDX components export
+				if (id.endsWith('mdx')) {
+					props = {
+						components: propagationMod.components ?? {},
+						...baseProps,
+					};
+				}
 
-			return createHeadAndContent(
-				unescapeHTML(styles + links + scripts) as any,
-				renderTemplate`${renderComponent(result, 'Content', mod.Content, props, slots)}`
-			);
-		},
-		propagation: 'self',
-	});
+				return createHeadAndContent(
+					unescapeHTML(styles + links + scripts) as any,
+					renderTemplate`${renderComponent(
+						result,
+						'Content',
+						propagationMod.Content,
+						props,
+						slots
+					)}`
+				);
+			},
+			propagation: 'self',
+		});
 
-	return {
-		Content,
-		headings: mod.getHeadings?.() ?? [],
-		remarkPluginFrontmatter: mod.frontmatter ?? {},
-	};
+		return {
+			Content,
+			headings: propagationMod.getHeadings?.() ?? [],
+			remarkPluginFrontmatter: propagationMod.frontmatter ?? {},
+		};
+	} else if (baseMod.Content && typeof baseMod.Content === 'function') {
+		return {
+			Content: baseMod.Content,
+			headings: baseMod.getHeadings?.() ?? [],
+			remarkPluginFrontmatter: baseMod.frontmatter ?? {},
+		};
+	} else {
+		throw UnexpectedRenderError;
+	}
 }
 
 export function createReference({ lookupMap }: { lookupMap: ContentLookupMap }) {
@@ -362,3 +379,15 @@ export function createReference({ lookupMap }: { lookupMap: ContentLookupMap })
 		});
 	};
 }
+
+type PropagatedAssetsModule = {
+	__astroPropagation: true;
+	getMod: () => Promise<any>;
+	collectedStyles: string[];
+	collectedLinks: string[];
+	collectedScripts: string[];
+};
+
+function isPropagatedAssetsModule(module: any): module is PropagatedAssetsModule {
+	return typeof module === 'object' && module != null && '__astroPropagation' in module;
+}
diff --git a/packages/astro/src/content/template/virtual-mod.mjs b/packages/astro/src/content/template/virtual-mod.mjs
index 491e594a6..e0ac7a564 100644
--- a/packages/astro/src/content/template/virtual-mod.mjs
+++ b/packages/astro/src/content/template/virtual-mod.mjs
@@ -46,7 +46,7 @@ function createGlobLookup(glob) {
 }
 
 const renderEntryGlob = import.meta.glob('@@RENDER_ENTRY_GLOB_PATH@@', {
-	query: { astroPropagatedAssets: true },
+	query: { astroRenderContent: true },
 });
 const collectionToRenderEntryMap = createCollectionToGlobResultMap({
 	globResult: renderEntryGlob,
diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index 40b2ab9e7..3cee0765c 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -15,6 +15,7 @@ import type {
 } from '../@types/astro.js';
 import { VALID_INPUT_FORMATS } from '../assets/consts.js';
 import { AstroError, AstroErrorData } from '../core/errors/index.js';
+
 import { formatYAMLException, isYAMLException } from '../core/errors/utils.js';
 import { CONTENT_FLAGS, CONTENT_TYPES_FILE } from './consts.js';
 import { errorMap } from './error-map.js';
@@ -331,7 +332,7 @@ export function parseFrontmatter(fileContents: string, filePath: string) {
  */
 export const globalContentConfigObserver = contentObservable({ status: 'init' });
 
-export function hasContentFlag(viteId: string, flag: (typeof CONTENT_FLAGS)[number]) {
+export function hasContentFlag(viteId: string, flag: (typeof CONTENT_FLAGS)[number]): boolean {
 	const flags = new URLSearchParams(viteId.split('?')[1] ?? '');
 	return flags.has(flag);
 }
diff --git a/packages/astro/src/content/vite-plugin-content-assets.ts b/packages/astro/src/content/vite-plugin-content-assets.ts
index 7e73f9f6b..bbd9749a8 100644
--- a/packages/astro/src/content/vite-plugin-content-assets.ts
+++ b/packages/astro/src/content/vite-plugin-content-assets.ts
@@ -1,4 +1,5 @@
-import { pathToFileURL } from 'url';
+import { extname } from 'node:path';
+import { pathToFileURL } from 'node:url';
 import type { Plugin } from 'vite';
 import type { AstroSettings } from '../@types/astro.js';
 import { moduleIsTopLevelPage, walkParentInfos } from '../core/build/graph.js';
@@ -11,16 +12,13 @@ import { joinPaths, prependForwardSlash } from '../core/path.js';
 import { getStylesForURL } from '../core/render/dev/css.js';
 import { getScriptsForURL } from '../core/render/dev/scripts.js';
 import {
+	CONTENT_RENDER_FLAG,
 	LINKS_PLACEHOLDER,
 	PROPAGATED_ASSET_FLAG,
 	SCRIPTS_PLACEHOLDER,
 	STYLES_PLACEHOLDER,
 } from './consts.js';
-
-function isPropagatedAsset(viteId: string) {
-	const flags = new URLSearchParams(viteId.split('?')[1]);
-	return flags.has(PROPAGATED_ASSET_FLAG);
-}
+import { hasContentFlag } from './utils.js';
 
 export function astroContentAssetPropagationPlugin({
 	mode,
@@ -32,13 +30,31 @@ export function astroContentAssetPropagationPlugin({
 	let devModuleLoader: ModuleLoader;
 	return {
 		name: 'astro:content-asset-propagation',
+		enforce: 'pre',
+		async resolveId(id, importer, opts) {
+			if (hasContentFlag(id, CONTENT_RENDER_FLAG)) {
+				const base = id.split('?')[0];
+
+				for (const { extensions, handlePropagation = true } of settings.contentEntryTypes) {
+					if (handlePropagation && extensions.includes(extname(base))) {
+						return this.resolve(`${base}?${PROPAGATED_ASSET_FLAG}`, importer, {
+							skipSelf: true,
+							...opts,
+						});
+					}
+				}
+				// Resolve to the base id (no content flags)
+				// if Astro doesn't need to handle propagation.
+				return this.resolve(base, importer, { skipSelf: true, ...opts });
+			}
+		},
 		configureServer(server) {
 			if (mode === 'dev') {
 				devModuleLoader = createViteLoader(server);
 			}
 		},
 		async transform(_, id, options) {
-			if (isPropagatedAsset(id)) {
+			if (hasContentFlag(id, PROPAGATED_ASSET_FLAG)) {
 				const basePath = id.split('?')[0];
 				let stringifiedLinks: string, stringifiedStyles: string, stringifiedScripts: string;
 
@@ -73,14 +89,17 @@ export function astroContentAssetPropagationPlugin({
 				}
 
 				const code = `
-					export async function getMod() {
+					async function getMod() {
 						return import(${JSON.stringify(basePath)});
 					}
-					export const collectedLinks = ${stringifiedLinks};
-					export const collectedStyles = ${stringifiedStyles};
-					export const collectedScripts = ${stringifiedScripts};
+					const collectedLinks = ${stringifiedLinks};
+					const collectedStyles = ${stringifiedStyles};
+					const collectedScripts = ${stringifiedScripts};
+					const defaultMod = { __astroPropagation: true, getMod, collectedLinks, collectedStyles, collectedScripts };
+					export default defaultMod;
 				`;
-
+				// ^ Use a default export for tools like Markdoc
+				// to catch the `__astroPropagation` identifier
 				return { code, map: { mappings: '' } };
 			}
 		},
diff --git a/packages/astro/src/core/render/dev/vite.ts b/packages/astro/src/core/render/dev/vite.ts
index 724ad172f..8d9baafa2 100644
--- a/packages/astro/src/core/render/dev/vite.ts
+++ b/packages/astro/src/core/render/dev/vite.ts
@@ -1,7 +1,6 @@
 import type { ModuleLoader, ModuleNode } from '../../module-loader/index';
 
 import npath from 'path';
-import { PROPAGATED_ASSET_FLAG } from '../../../content/consts.js';
 import { SUPPORTED_MARKDOWN_FILE_EXTENSIONS } from '../../constants.js';
 import { unwrapId } from '../../util.js';
 import { isCSSRequest } from './util.js';
@@ -10,9 +9,10 @@ import { isCSSRequest } from './util.js';
  * List of file extensions signalling we can (and should) SSR ahead-of-time
  * See usage below
  */
-const fileExtensionsToSSR = new Set(['.astro', ...SUPPORTED_MARKDOWN_FILE_EXTENSIONS]);
+const fileExtensionsToSSR = new Set(['.astro', '.mdoc', ...SUPPORTED_MARKDOWN_FILE_EXTENSIONS]);
 
 const STRIP_QUERY_PARAMS_REGEX = /\?.*$/;
+const ASTRO_PROPAGATED_ASSET_REGEX = /\?astroPropagatedAssets/;
 
 /** recursively crawl the module graph to get all style files imported by parent id */
 export async function* crawlGraph(
@@ -23,7 +23,6 @@ export async function* crawlGraph(
 ): AsyncGenerator<ModuleNode, void, unknown> {
 	const id = unwrapId(_id);
 	const importedModules = new Set<ModuleNode>();
-	if (new URL(id, 'file://').searchParams.has(PROPAGATED_ASSET_FLAG)) return;
 
 	const moduleEntriesForId = isRootFile
 		? // "getModulesByFile" pulls from a delayed module cache (fun implementation detail),
@@ -44,7 +43,11 @@ export async function* crawlGraph(
 		if (id === entry.id) {
 			scanned.add(id);
 			const entryIsStyle = isCSSRequest(id);
+
 			for (const importedModule of entry.importedModules) {
+				// A propagation stopping point is a module with the ?astroPropagatedAssets flag.
+				// When we encounter one of these modules we don't want to continue traversing.
+				let isPropagationStoppingPoint = false;
 				// some dynamically imported modules are *not* server rendered in time
 				// to only SSR modules that we can safely transform, we check against
 				// a list of file extensions based on our built-in vite plugins
@@ -60,15 +63,14 @@ export async function* crawlGraph(
 					if (entryIsStyle && !isCSSRequest(importedModulePathname)) {
 						continue;
 					}
+					const isFileTypeNeedingSSR = fileExtensionsToSSR.has(
+						npath.extname(importedModulePathname)
+					);
+					isPropagationStoppingPoint = ASTRO_PROPAGATED_ASSET_REGEX.test(importedModule.id);
 					if (
-						fileExtensionsToSSR.has(
-							npath.extname(
-								// Use `id` instead of `pathname` to preserve query params.
-								// Should not SSR a module with an unexpected query param,
-								// like "?astroPropagatedAssets"
-								importedModule.id
-							)
-						)
+						isFileTypeNeedingSSR &&
+						// Should not SSR a module with ?astroPropagatedAssets
+						!isPropagationStoppingPoint
 					) {
 						const mod = loader.getModuleById(importedModule.id);
 						if (!mod?.ssrModule) {
@@ -80,7 +82,9 @@ export async function* crawlGraph(
 						}
 					}
 				}
-				importedModules.add(importedModule);
+				if(!isPropagationStoppingPoint) {
+					importedModules.add(importedModule);
+				}
 			}
 		}
 	}
diff --git a/packages/astro/src/vite-plugin-head/index.ts b/packages/astro/src/vite-plugin-head/index.ts
index fc19893e8..4f44aaf6e 100644
--- a/packages/astro/src/vite-plugin-head/index.ts
+++ b/packages/astro/src/vite-plugin-head/index.ts
@@ -9,7 +9,8 @@ import { getTopLevelPages, walkParentInfos } from '../core/build/graph.js';
 import type { BuildInternals } from '../core/build/internal.js';
 import { getAstroMetadata } from '../vite-plugin-astro/index.js';
 
-const injectExp = /^\/\/\s*astro-head-inject/;
+// Detect this in comments, both in .astro components and in js/ts files.
+const injectExp = /(^\/\/|\/\/!)\s*astro-head-inject/;
 
 export default function configHeadVitePlugin({
 	settings,
@@ -32,6 +33,7 @@ export default function configHeadVitePlugin({
 		seen.add(id);
 		const mod = server.moduleGraph.getModuleById(id);
 		const info = this.getModuleInfo(id);
+
 		if (info?.meta.astro) {
 			const astroMetadata = getAstroMetadata(info);
 			if (astroMetadata) {
diff --git a/packages/astro/src/vite-plugin-markdown/content-entry-type.ts b/packages/astro/src/vite-plugin-markdown/content-entry-type.ts
index cbf5cc957..a3489c940 100644
--- a/packages/astro/src/vite-plugin-markdown/content-entry-type.ts
+++ b/packages/astro/src/vite-plugin-markdown/content-entry-type.ts
@@ -13,6 +13,8 @@ export const markdownContentEntryType: ContentEntryType = {
 			rawData: parsed.matter,
 		};
 	},
+	// We need to handle propagation for Markdown because they support layouts which will bring in styles.
+	handlePropagation: true,
 };
 
 /**
@@ -30,6 +32,9 @@ export const mdxContentEntryType: ContentEntryType = {
 			rawData: parsed.matter,
 		};
 	},
+	// MDX can import scripts and styles,
+	// so wrap all MDX files with script / style propagation checks
+	handlePropagation: true,
 	contentModuleTypes: `declare module 'astro:content' {
 	interface Render {
 		'.mdx': Promise<{
diff --git a/packages/integrations/markdoc/components/Renderer.astro b/packages/integrations/markdoc/components/Renderer.astro
index 5e2b6833a..6571e8c71 100644
--- a/packages/integrations/markdoc/components/Renderer.astro
+++ b/packages/integrations/markdoc/components/Renderer.astro
@@ -1,4 +1,5 @@
 ---
+//! astro-head-inject
 import type { Config } from '@markdoc/markdoc';
 import Markdoc from '@markdoc/markdoc';
 import { ComponentNode, createTreeNode } from './TreeNode.js';
@@ -14,4 +15,4 @@ const ast = Markdoc.Ast.fromJSON(stringifiedAst);
 const content = Markdoc.transform(ast, config);
 ---
 
-<ComponentNode treeNode={createTreeNode(content)} />
+<ComponentNode treeNode={await createTreeNode(content)} />
diff --git a/packages/integrations/markdoc/components/TreeNode.ts b/packages/integrations/markdoc/components/TreeNode.ts
index d12180a18..8ad778063 100644
--- a/packages/integrations/markdoc/components/TreeNode.ts
+++ b/packages/integrations/markdoc/components/TreeNode.ts
@@ -6,6 +6,11 @@ import {
 	createComponent,
 	renderComponent,
 	render,
+	renderScriptElement,
+	renderUniqueStylesheet,
+	createHeadAndContent,
+	unescapeHTML,
+	renderTemplate,
 	HTMLString,
 	isHTMLString,
 } from 'astro/runtime/server/index.js';
@@ -18,6 +23,9 @@ export type TreeNode =
 	| {
 			type: 'component';
 			component: AstroInstance['default'];
+			collectedLinks?: string[];
+			collectedStyles?: string[];
+			collectedScripts?: string[];
 			props: Record<string, any>;
 			children: TreeNode[];
 	  }
@@ -39,20 +47,66 @@ export const ComponentNode = createComponent({
 				)}`,
 		};
 		if (treeNode.type === 'component') {
-			return renderComponent(
-				result,
-				treeNode.component.name,
-				treeNode.component,
-				treeNode.props,
-				slots
+			let styles = '',
+				links = '',
+				scripts = '';
+			if (Array.isArray(treeNode.collectedStyles)) {
+				styles = treeNode.collectedStyles
+					.map((style: any) =>
+						renderUniqueStylesheet(result, {
+							type: 'inline',
+							content: style,
+						})
+					)
+					.join('');
+			}
+			if (Array.isArray(treeNode.collectedLinks)) {
+				links = treeNode.collectedLinks
+					.map((link: any) => {
+						return renderUniqueStylesheet(result, {
+							type: 'external',
+							src: link[0] === '/' ? link : '/' + link,
+						});
+					})
+					.join('');
+			}
+			if (Array.isArray(treeNode.collectedScripts)) {
+				scripts = treeNode.collectedScripts
+					.map((script: any) => renderScriptElement(script))
+					.join('');
+			}
+
+			const head = unescapeHTML(styles + links + scripts);
+
+			let headAndContent = createHeadAndContent(
+				head,
+				renderTemplate`${renderComponent(
+					result,
+					treeNode.component.name,
+					treeNode.component,
+					treeNode.props,
+					slots
+				)}`
 			);
+
+			// Let the runtime know that this component is being used.
+			result.propagators.set(
+				{},
+				{
+					init() {
+						return headAndContent;
+					},
+				}
+			);
+
+			return headAndContent;
 		}
 		return renderComponent(result, treeNode.tag, treeNode.tag, treeNode.attributes, slots);
 	},
-	propagation: 'none',
+	propagation: 'self',
 });
 
-export function createTreeNode(node: RenderableTreeNode | RenderableTreeNode[]): TreeNode {
+export async function createTreeNode(node: RenderableTreeNode | RenderableTreeNode[]): TreeNode {
 	if (isHTMLString(node)) {
 		return { type: 'text', content: node as HTMLString };
 	} else if (typeof node === 'string' || typeof node === 'number') {
@@ -62,16 +116,17 @@ export function createTreeNode(node: RenderableTreeNode | RenderableTreeNode[]):
 			type: 'component',
 			component: Fragment,
 			props: {},
-			children: node.map((child) => createTreeNode(child)),
+			children: await Promise.all(node.map((child) => createTreeNode(child))),
 		};
 	} else if (node === null || typeof node !== 'object' || !Markdoc.Tag.isTag(node)) {
 		return { type: 'text', content: '' };
 	}
 
+	const children = await Promise.all(node.children.map((child) => createTreeNode(child)));
+
 	if (typeof node.name === 'function') {
 		const component = node.name;
 		const props = node.attributes;
-		const children = node.children.map((child) => createTreeNode(child));
 
 		return {
 			type: 'component',
@@ -79,12 +134,38 @@ export function createTreeNode(node: RenderableTreeNode | RenderableTreeNode[]):
 			props,
 			children,
 		};
+	} else if (isPropagatedAssetsModule(node.name)) {
+		const { collectedStyles, collectedLinks, collectedScripts } = node.name;
+		const component = (await node.name.getMod())?.default ?? Fragment;
+		const props = node.attributes;
+
+		return {
+			type: 'component',
+			component,
+			collectedStyles,
+			collectedLinks,
+			collectedScripts,
+			props,
+			children,
+		};
 	} else {
 		return {
 			type: 'element',
 			tag: node.name,
 			attributes: node.attributes,
-			children: node.children.map((child) => createTreeNode(child)),
+			children,
 		};
 	}
 }
+
+type PropagatedAssetsModule = {
+	__astroPropagation: true;
+	getMod: () => Promise<AstroInstance['default']>;
+	collectedStyles: string[];
+	collectedLinks: string[];
+	collectedScripts: string[];
+};
+
+function isPropagatedAssetsModule(module: any): module is PropagatedAssetsModule {
+	return typeof module === 'object' && module != null && '__astroPropagation' in module;
+}
diff --git a/packages/integrations/markdoc/src/heading-ids.ts b/packages/integrations/markdoc/src/heading-ids.ts
index 5c2f197f2..5e54af9a7 100644
--- a/packages/integrations/markdoc/src/heading-ids.ts
+++ b/packages/integrations/markdoc/src/heading-ids.ts
@@ -47,13 +47,14 @@ export const heading: Schema = {
 		const slug = getSlug(attributes, children, config.ctx.headingSlugger);
 
 		const render = config.nodes?.heading?.render ?? `h${level}`;
+
 		const tagProps =
 			// For components, pass down `level` as a prop,
 			// alongside `__collectHeading` for our `headings` collector.
 			// Avoid accidentally rendering `level` as an HTML attribute otherwise!
-			typeof render === 'function'
-				? { ...attributes, id: slug, __collectHeading: true, level }
-				: { ...attributes, id: slug };
+			typeof render === 'string'
+				? { ...attributes, id: slug }
+				: { ...attributes, id: slug, __collectHeading: true, level };
 
 		return new Markdoc.Tag(render, tagProps, children);
 	},
diff --git a/packages/integrations/markdoc/src/index.ts b/packages/integrations/markdoc/src/index.ts
index f33c3a1be..5bcd8dff3 100644
--- a/packages/integrations/markdoc/src/index.ts
+++ b/packages/integrations/markdoc/src/index.ts
@@ -4,7 +4,15 @@ import Markdoc from '@markdoc/markdoc';
 import type { AstroConfig, AstroIntegration, ContentEntryType, HookParameters } from 'astro';
 import fs from 'node:fs';
 import { fileURLToPath, pathToFileURL } from 'node:url';
-import { isValidUrl, MarkdocError, parseFrontmatter, prependForwardSlash } from './utils.js';
+import {
+	createNameHash,
+	hasContentFlag,
+	isValidUrl,
+	MarkdocError,
+	parseFrontmatter,
+	prependForwardSlash,
+	PROPAGATED_ASSET_FLAG,
+} from './utils.js';
 // @ts-expect-error Cannot find module 'astro/assets' or its corresponding type declarations.
 import { emitESMImage } from 'astro/assets';
 import { bold, red, yellow } from 'kleur/colors';
@@ -12,6 +20,7 @@ import path from 'node:path';
 import type * as rollup from 'rollup';
 import { loadMarkdocConfig, type MarkdocConfigResult } from './load-config.js';
 import { setupConfig } from './runtime.js';
+import { normalizePath } from 'vite';
 
 type SetupHookParams = HookParameters<'astro:config:setup'> & {
 	// `contentEntryType` is not a public API
@@ -35,6 +44,7 @@ export default function markdocIntegration(legacyConfig?: any): AstroIntegration
 		process.exit(0);
 	}
 	let markdocConfigResult: MarkdocConfigResult | undefined;
+	let markdocConfigResultId = '';
 	return {
 		name: '@astrojs/markdoc',
 		hooks: {
@@ -45,15 +55,10 @@ export default function markdocIntegration(legacyConfig?: any): AstroIntegration
 					addContentEntryType,
 				} = params as SetupHookParams;
 
-				updateConfig({
-					vite: {
-						ssr: {
-							external: ['@astrojs/markdoc/prism', '@astrojs/markdoc/shiki'],
-						},
-					},
-				});
-
 				markdocConfigResult = await loadMarkdocConfig(astroConfig);
+				if(markdocConfigResult) {
+					markdocConfigResultId = normalizePath(fileURLToPath(markdocConfigResult.fileUrl));
+				}
 				const userMarkdocConfig = markdocConfigResult?.config ?? {};
 
 				function getEntryInfo({ fileUrl, contents }: { fileUrl: URL; contents: string }) {
@@ -68,6 +73,9 @@ export default function markdocIntegration(legacyConfig?: any): AstroIntegration
 				addContentEntryType({
 					extensions: ['.mdoc'],
 					getEntryInfo,
+					// Markdoc handles script / style propagation
+					// for Astro components internally
+					handlePropagation: false,
 					async getRenderModule({ contents, fileUrl, viteId }) {
 						const entry = getEntryInfo({ contents, fileUrl });
 						const tokens = markdocTokenizer.tokenize(entry.body);
@@ -112,14 +120,16 @@ export default function markdocIntegration(legacyConfig?: any): AstroIntegration
 							});
 						}
 
-						const res = `import { jsx as h } from 'astro/jsx-runtime';
+						const res = `import {
+							createComponent,
+							renderComponent,
+						} from 'astro/runtime/server/index.js';
 						import { Renderer } from '@astrojs/markdoc/components';
 						import { collectHeadings, setupConfig, setupConfigSync, Markdoc } from '@astrojs/markdoc/runtime';
-import * as entry from ${JSON.stringify(viteId + '?astroContentCollectionEntry')};
 ${
 	markdocConfigResult
 		? `import _userConfig from ${JSON.stringify(
-				markdocConfigResult.fileUrl.pathname
+			markdocConfigResultId
 		  )};\nconst userConfig = _userConfig ?? {};`
 		: 'const userConfig = {};'
 }${
@@ -138,19 +148,29 @@ export function getHeadings() {
 		''
 	}
 	const headingConfig = userConfig.nodes?.heading;
-	const config = setupConfigSync(headingConfig ? { nodes: { heading: headingConfig } } : {}, entry);
+	const config = setupConfigSync(headingConfig ? { nodes: { heading: headingConfig } } : {});
 	const ast = Markdoc.Ast.fromJSON(stringifiedAst);
 	const content = Markdoc.transform(ast, config);
 	return collectHeadings(Array.isArray(content) ? content : content.children);
 }
-export async function Content (props) {
-	const config = await setupConfig({
-		...userConfig,
-		variables: { ...userConfig.variables, ...props },
-	}, entry);
 
-	return h(Renderer, { config, stringifiedAst });
-}`;
+export const Content = createComponent({
+	async factory(result, props) {
+		const config = await setupConfig({
+			...userConfig,
+			variables: { ...userConfig.variables, ...props },
+		});
+		
+		return renderComponent(
+			result,
+			Renderer.name,
+			Renderer,
+			{ stringifiedAst, config },
+			{}
+		);
+	},
+	propagation: 'self',
+});`;
 						return { code: res };
 					},
 					contentModuleTypes: await fs.promises.readFile(
@@ -158,10 +178,58 @@ export async function Content (props) {
 						'utf-8'
 					),
 				});
+
+				let rollupOptions: rollup.RollupOptions = {};
+				if (markdocConfigResult) {
+					rollupOptions = {
+						output: {
+							// Split Astro components from your `markdoc.config`
+							// to only inject component styles and scripts at runtime.
+							manualChunks(id, { getModuleInfo }) {
+								if (
+									markdocConfigResult &&
+									hasContentFlag(id, PROPAGATED_ASSET_FLAG) &&
+									getModuleInfo(id)?.importers?.includes(markdocConfigResultId)
+								) {
+									return createNameHash(id, [id]);
+								}
+							},
+						},
+					};
+				}
+
+				updateConfig({
+					vite: {
+						vite: {
+							ssr: {
+								external: ['@astrojs/markdoc/prism', '@astrojs/markdoc/shiki'],
+							},
+						},
+						build: {
+							rollupOptions,
+						},
+						plugins: [
+							{
+								name: '@astrojs/markdoc:astro-propagated-assets',
+								enforce: 'pre',
+								// Astro component styles and scripts should only be injected
+								// When a given Markdoc file actually uses that component.
+								// Add the `astroPropagatedAssets` flag to inject only when rendered.
+								resolveId(this: rollup.TransformPluginContext, id: string, importer: string) {
+									if (importer === markdocConfigResultId && id.endsWith('.astro')) {
+										return this.resolve(id + '?astroPropagatedAssets', importer, {
+											skipSelf: true,
+										});
+									}
+								},
+							},
+						],
+					},
+				});
 			},
 			'astro:server:setup': async ({ server }) => {
 				server.watcher.on('all', (event, entry) => {
-					if (pathToFileURL(entry).pathname === markdocConfigResult?.fileUrl.pathname) {
+					if (prependForwardSlash(pathToFileURL(entry).pathname) === markdocConfigResultId) {
 						console.log(
 							yellow(
 								`${bold('[Markdoc]')} Restart the dev server for config changes to take effect.`
diff --git a/packages/integrations/markdoc/src/runtime.ts b/packages/integrations/markdoc/src/runtime.ts
index a1861c68c..bbbd85739 100644
--- a/packages/integrations/markdoc/src/runtime.ts
+++ b/packages/integrations/markdoc/src/runtime.ts
@@ -32,13 +32,9 @@ export async function setupConfig(
 
 /** Used for synchronous `getHeadings()` function */
 export function setupConfigSync(
-	userConfig: AstroMarkdocConfig,
-	entry: ContentEntryModule
+	userConfig: AstroMarkdocConfig
 ): Omit<AstroMarkdocConfig, 'extends'> {
-	let defaultConfig: AstroMarkdocConfig = {
-		...setupHeadingConfig(),
-		variables: { entry },
-	};
+	const defaultConfig: AstroMarkdocConfig = setupHeadingConfig();
 
 	return mergeConfig(defaultConfig, userConfig);
 }
diff --git a/packages/integrations/markdoc/src/utils.ts b/packages/integrations/markdoc/src/utils.ts
index ea5dda6db..ad964f56c 100644
--- a/packages/integrations/markdoc/src/utils.ts
+++ b/packages/integrations/markdoc/src/utils.ts
@@ -1,3 +1,5 @@
+import crypto from 'node:crypto';
+import path from 'node:path';
 import matter from 'gray-matter';
 import type { ErrorPayload as ViteErrorPayload } from 'vite';
 
@@ -96,3 +98,32 @@ export function isValidUrl(str: string): boolean {
 		return false;
 	}
 }
+
+/**
+ * Identifies Astro components with propagated assets
+ * @see 'packages/astro/src/content/consts.ts'
+ */
+export const PROPAGATED_ASSET_FLAG = 'astroPropagatedAssets';
+
+/**
+ * @see 'packages/astro/src/content/utils.ts'
+ */
+export function hasContentFlag(viteId: string, flag: string): boolean {
+	const flags = new URLSearchParams(viteId.split('?')[1] ?? '');
+	return flags.has(flag);
+}
+
+/**
+ * Create build hash for manual Rollup chunks.
+ * @see 'packages/astro/src/core/build/plugins/plugin-css.ts'
+ */
+export function createNameHash(baseId: string, hashIds: string[]): string {
+	const baseName = baseId ? path.parse(baseId).name : 'index';
+	const hash = crypto.createHash('sha256');
+	for (const id of hashIds) {
+		hash.update(id, 'utf-8');
+	}
+	const h = hash.digest('hex').slice(0, 8);
+	const proposedName = baseName + '.' + h;
+	return proposedName;
+}
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/astro.config.mjs b/packages/integrations/markdoc/test/fixtures/propagated-assets/astro.config.mjs
new file mode 100644
index 000000000..29d846359
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/astro.config.mjs
@@ -0,0 +1,7 @@
+import { defineConfig } from 'astro/config';
+import markdoc from '@astrojs/markdoc';
+
+// https://astro.build/config
+export default defineConfig({
+	integrations: [markdoc()],
+});
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/markdoc.config.mjs b/packages/integrations/markdoc/test/fixtures/propagated-assets/markdoc.config.mjs
new file mode 100644
index 000000000..5389eb99d
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/markdoc.config.mjs
@@ -0,0 +1,18 @@
+import Aside from './src/components/Aside.astro';
+import LogHello from './src/components/LogHello.astro';
+import { defineMarkdocConfig } from '@astrojs/markdoc/config';
+
+export default defineMarkdocConfig({
+	tags: {
+		aside: {
+			render: Aside,
+			attributes: {
+				type: { type: String },
+				title: { type: String },
+			}
+		},
+		logHello: {
+			render: LogHello,
+		}
+	},
+})
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/package.json b/packages/integrations/markdoc/test/fixtures/propagated-assets/package.json
new file mode 100644
index 000000000..3b51e158d
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "@test/markdoc-propagated-assets",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "@astrojs/markdoc": "workspace:*",
+    "astro": "workspace:*"
+  }
+}
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/src/components/Aside.astro b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/components/Aside.astro
new file mode 100644
index 000000000..5d92a0993
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/components/Aside.astro
@@ -0,0 +1,116 @@
+---
+// Inspired by the `Aside` component from docs.astro.build
+// https://github.com/withastro/docs/blob/main/src/components/Aside.astro
+
+export interface Props {
+	type?: 'note' | 'tip' | 'caution' | 'danger';
+	title?: string;
+}
+
+const labelByType = {
+	note: 'Note',
+	tip: 'Tip',
+	caution: 'Caution',
+	danger: 'Danger',
+};
+const { type = 'note' } = Astro.props as Props;
+const title = Astro.props.title ?? labelByType[type] ?? '';
+
+// SVG icon paths based on GitHub Octicons
+const icons: Record<NonNullable<Props['type']>, { viewBox: string; d: string }> = {
+	note: {
+		viewBox: '0 0 18 18',
+		d: 'M0 3.75C0 2.784.784 2 1.75 2h12.5c.966 0 1.75.784 1.75 1.75v8.5A1.75 1.75 0 0114.25 14H1.75A1.75 1.75 0 010 12.25v-8.5zm1.75-.25a.25.25 0 00-.25.25v8.5c0 .138.112.25.25.25h12.5a.25.25 0 00.25-.25v-8.5a.25.25 0 00-.25-.25H1.75zM3.5 6.25a.75.75 0 01.75-.75h7a.75.75 0 010 1.5h-7a.75.75 0 01-.75-.75zm.75 2.25a.75.75 0 000 1.5h4a.75.75 0 000-1.5h-4z',
+	},
+	tip: {
+		viewBox: '0 0 18 18',
+		d: 'M14 0a8.8 8.8 0 0 0-6 2.6l-.5.4-.9 1H3.3a1.8 1.8 0 0 0-1.5.8L.1 7.6a.8.8 0 0 0 .4 1.1l3.1 1 .2.1 2.4 2.4.1.2 1 3a.8.8 0 0 0 1 .5l2.9-1.7a1.8 1.8 0 0 0 .8-1.5V9.5l1-1 .4-.4A8.8 8.8 0 0 0 16 2v-.1A1.8 1.8 0 0 0 14.2 0h-.1zm-3.5 10.6-.3.2L8 12.3l.5 1.8 2-1.2a.3.3 0 0 0 .1-.2v-2zM3.7 8.1l1.5-2.3.2-.3h-2a.3.3 0 0 0-.3.1l-1.2 2 1.8.5zm5.2-4.5a7.3 7.3 0 0 1 5.2-2.1h.1a.3.3 0 0 1 .3.3v.1a7.3 7.3 0 0 1-2.1 5.2l-.5.4a15.2 15.2 0 0 1-2.5 2L7.1 11 5 9l1.5-2.3a15.3 15.3 0 0 1 2-2.5l.4-.5zM12 5a1 1 0 1 1-2 0 1 1 0 0 1 2 0zm-8.4 9.6a1.5 1.5 0 1 0-2.2-2.2 7 7 0 0 0-1.1 3 .2.2 0 0 0 .3.3c.6 0 2.2-.4 3-1.1z',
+	},
+	caution: {
+		viewBox: '-1 1 18 18',
+		d: 'M8.9 1.5C8.7 1.2 8.4 1 8 1s-.7.2-.9.5l-7 12a1 1 0 0 0 0 1c.2.3.6.5 1 .5H15c.4 0 .7-.2.9-.5a1 1 0 0 0 0-1l-7-12zM9 13H7v-2h2v2zm0-3H7V6h2v4z',
+	},
+	danger: {
+		viewBox: '0 1 14 17',
+		d: 'M5 .3c.9 2.2.5 3.4-.5 4.3C3.5 5.6 2 6.5 1 8c-1.5 2-1.7 6.5 3.5 7.7-2.2-1.2-2.6-4.5-.3-6.6-.6 2 .6 3.3 2 2.8 1.4-.4 2.3.6 2.2 1.7 0 .8-.3 1.4-1 1.8A5.6 5.6 0 0 0 12 10c0-2.9-2.5-3.3-1.3-5.7-1.5.2-2 1.2-1.8 2.8 0 1-1 1.8-2 1.3-.6-.4-.6-1.2 0-1.8C8.2 5.3 8.7 2.5 5 .3z',
+	},
+};
+const { viewBox, d } = icons[type];
+---
+
+<aside class={`content ${type}`} aria-label={title}>
+	<p class="title" aria-hidden="true">
+		<span class="icon">
+			<svg xmlns="http://www.w3.org/2000/svg" viewBox={viewBox} width={16} height={16}>
+				<path fill-rule="evenodd" d={d}></path>
+			</svg>
+		</span>
+		{title}
+	</p>
+	<section>
+		<slot />
+	</section>
+</aside>
+
+<style>
+	aside {
+		--color-base-purple: 269, 79%;
+		--color-base-teal: 180, 80%;
+		--color-base-red: 351, 100%;
+		--color-base-yellow: 41, 100%;
+
+		--aside-color-base: var(--color-base-purple);
+		--aside-color-lightness: 54%;
+		--aside-accent-color: hsl(var(--aside-color-base), var(--aside-color-lightness));
+		--aside-text-lightness: 20%;
+		--aside-text-accent-color: hsl(var(--aside-color-base), var(--aside-text-lightness));
+
+		border-inline-start: 4px solid var(--aside-accent-color);
+		padding: 1rem;
+		background-color: hsla(var(--aside-color-base), var(--aside-color-lightness), 0.1);
+		/* Indicates the aside boundaries for forced colors users, transparent is changed to a solid color */
+		outline: 1px solid transparent;
+	}
+
+	.title {
+		line-height: 1;
+		margin-bottom: 0.5rem;
+		font-size: 0.9rem;
+		letter-spacing: 0.05em;
+		font-weight: bold;
+		text-transform: uppercase;
+		color: var(--aside-text-accent-color);
+	}
+
+	.icon svg {
+		width: 1.5em;
+		height: 1.5em;
+		vertical-align: middle;
+		fill: currentcolor;
+	}
+
+	aside :global(a),
+	aside :global(a > code:not([class*='language'])) {
+		color: var(--aside-text-accent-color);
+	}
+
+	aside :global(pre) {
+		margin-left: 0;
+		margin-right: 0;
+	}
+
+	.tip {
+		--aside-color-lightness: 42%;
+		--aside-color-base: var(--color-base-teal);
+	}
+
+	.caution {
+		--aside-color-lightness: 59%;
+		--aside-color-base: var(--color-base-yellow);
+	}
+
+	.danger {
+		--aside-color-lightness: 54%;
+		--aside-color-base: var(--color-base-red);
+	}
+</style>
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/src/components/LogHello.astro b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/components/LogHello.astro
new file mode 100644
index 000000000..6d994378b
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/components/LogHello.astro
@@ -0,0 +1,5 @@
+<p>I'm gonna log hello</p>
+
+<script>
+	console.log('hello');
+</script>
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/src/content/blog/scripts.mdoc b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/content/blog/scripts.mdoc
new file mode 100644
index 000000000..808cffaca
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/content/blog/scripts.mdoc
@@ -0,0 +1,5 @@
+---
+title: Scripts
+---
+
+{% logHello /%}
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/src/content/blog/styles.mdoc b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/content/blog/styles.mdoc
new file mode 100644
index 000000000..20960e4cf
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/content/blog/styles.mdoc
@@ -0,0 +1,9 @@
+---
+title: Styles
+---
+
+{% aside type="tip" %}
+
+## Example
+
+{% /aside %}
diff --git a/packages/integrations/markdoc/test/fixtures/propagated-assets/src/pages/[slug].astro b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/pages/[slug].astro
new file mode 100644
index 000000000..baee15375
--- /dev/null
+++ b/packages/integrations/markdoc/test/fixtures/propagated-assets/src/pages/[slug].astro
@@ -0,0 +1,26 @@
+---
+import { getCollection } from 'astro:content';
+
+export async function getStaticPaths() {
+	const posts = await getCollection('blog');
+	return posts.map((post) => ({
+		params: { slug: post.slug },
+		props: post,
+	}));
+}
+
+const { Content } = await Astro.props.render();
+---
+
+<!DOCTYPE html>
+<html lang="en">
+<head>
+	<meta charset="UTF-8">
+	<meta http-equiv="X-UA-Compatible" content="IE=edge">
+	<meta name="viewport" content="width=device-width, initial-scale=1.0">
+	<title>{Astro.props.data.title}</title>
+</head>
+<body>
+	<Content />	
+</body>
+</html>
diff --git a/packages/integrations/markdoc/test/propagated-assets.test.js b/packages/integrations/markdoc/test/propagated-assets.test.js
new file mode 100644
index 000000000..429e07141
--- /dev/null
+++ b/packages/integrations/markdoc/test/propagated-assets.test.js
@@ -0,0 +1,66 @@
+import { parseHTML } from 'linkedom';
+import { expect } from 'chai';
+import { loadFixture } from '../../../astro/test/test-utils.js';
+
+describe('Markdoc - propagated assets', () => {
+	let fixture;
+	let devServer;
+	before(async () => {
+		fixture = await loadFixture({
+			root: new URL('./fixtures/propagated-assets/', import.meta.url),
+		});
+	});
+
+	const modes = ['dev', 'prod'];
+
+	for (const mode of modes) {
+		describe(mode, () => {
+			/** @type {Document} */
+			let stylesDocument;
+			/** @type {Document} */
+			let scriptsDocument;
+
+			before(async () => {
+				if (mode === 'prod') {
+					await fixture.build();
+					stylesDocument = parseHTML(await fixture.readFile('/styles/index.html')).document;
+					scriptsDocument = parseHTML(await fixture.readFile('/scripts/index.html')).document;
+				} else if (mode === 'dev') {
+					devServer = await fixture.startDevServer();
+					const styleRes = await fixture.fetch('/styles');
+					const scriptRes = await fixture.fetch('/scripts');
+					stylesDocument = parseHTML(await styleRes.text()).document;
+					scriptsDocument = parseHTML(await scriptRes.text()).document;
+				}
+			});
+
+			after(async () => {
+				if (mode === 'dev') devServer?.stop();
+			});
+
+			it('Bundles styles', async () => {
+				let styleContents;
+				if (mode === 'dev') {
+					const styles = stylesDocument.querySelectorAll('style');
+					expect(styles).to.have.lengthOf(1);
+					styleContents = styles[0].textContent;
+				} else {
+					const links = stylesDocument.querySelectorAll('link[rel="stylesheet"]');
+					expect(links).to.have.lengthOf(1);
+					styleContents = await fixture.readFile(links[0].href);
+				}
+				expect(styleContents).to.include('--color-base-purple: 269, 79%;');
+			});
+
+			it('[fails] Does not bleed styles to other page', async () => {
+				if (mode === 'dev') {
+					const styles = scriptsDocument.querySelectorAll('style');
+					expect(styles).to.have.lengthOf(0);
+				} else {
+					const links = scriptsDocument.querySelectorAll('link[rel="stylesheet"]');
+					expect(links).to.have.lengthOf(0);
+				}
+			});
+		});
+	}
+});
diff --git a/packages/integrations/mdx/src/index.ts b/packages/integrations/mdx/src/index.ts
index e11cd1ac5..18c9aceca 100644
--- a/packages/integrations/mdx/src/index.ts
+++ b/packages/integrations/mdx/src/index.ts
@@ -56,6 +56,9 @@ export default function mdx(partialMdxOptions: Partial<MdxOptions> = {}): AstroI
 						new URL('../template/content-module-types.d.ts', import.meta.url),
 						'utf-8'
 					),
+					// MDX can import scripts and styles,
+					// so wrap all MDX files with script / style propagation checks
+					handlePropagation: true,
 				});
 
 				const extendMarkdownConfig =
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index a6f81bd15..dab25439a 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -4071,6 +4071,15 @@ importers:
         specifier: workspace:*
         version: link:../../../../../astro
 
+  packages/integrations/markdoc/test/fixtures/propagated-assets:
+    dependencies:
+      '@astrojs/markdoc':
+        specifier: workspace:*
+        version: link:../../..
+      astro:
+        specifier: workspace:*
+        version: link:../../../../../astro
+
   packages/integrations/markdoc/test/fixtures/render-null:
     dependencies:
       '@astrojs/markdoc':