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diff --git a/browser/components/storybook/.storybook/markdown-story-indexer.js b/browser/components/storybook/.storybook/markdown-story-indexer.js
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+/* eslint-env node */
+
+const { loadCsf } = require("@storybook/csf-tools");
+const { compile } = require("@storybook/mdx2-csf");
+const { getStoryTitle, getMDXSource } = require("./markdown-story-utils.js");
+const fs = require("fs");
+
+/**
+ * Function that tells Storybook how to index markdown based stories. This is
+ * responsible for Storybook knowing how to populate the sidebar in the
+ * Storybook UI, then retrieve the relevant file when a story is selected. In
+ * order to get the data Storybook needs, we have to convert the markdown to
+ * MDX, the convert that to CSF.
+ * More info on indexers can be found here: storybook.js.org/docs/api/main-config-indexers
+ * @param {string} fileName - Path to the file being processed.
+ * @param {Object} opts - Options to configure the indexer.
+ * @returns Array of IndexInput objects.
+ */
+module.exports = async (fileName, opts) => {
+  // eslint-disable-next-line no-unsanitized/method
+  const content = fs.readFileSync(fileName, "utf8");
+  const title = getStoryTitle(fileName);
+  const code = getMDXSource(content, title);
+
+  // Compile MDX into CSF
+  const csfCode = await compile(code, opts);
+
+  // Parse CSF component
+  let csf = loadCsf(csfCode, { fileName, makeTitle: () => title }).parse();
+
+  // Return an array of story indexes.
+  // Cribbed from https://github.com/storybookjs/storybook/blob/4169cd5b4ec9111de69f64a5e06edab9a6d2b0b8/code/addons/docs/src/preset.ts#L189
+  const { indexInputs, stories } = csf;
+  return indexInputs.map((input, index) => {
+    const docsOnly = stories[index].parameters?.docsOnly;
+    const tags = input.tags ? input.tags : [];
+    if (docsOnly) {
+      tags.push("stories-mdx-docsOnly");
+    }
+    // the mdx-csf compiler automatically adds the 'stories-mdx' tag to meta,
+    // here' we're just making sure it is always there
+    if (!tags.includes("stories-mdx")) {
+      tags.push("stories-mdx");
+    }
+    return { ...input, tags };
+  });
+};