fix(deps): use the Typography selector-parser security backport

docs/REFRESH-OPERATIONS.md

@@ -336,6 +336,41 @@ and this performance follow-up. Version 6.1.5 is the CSS parser, not Router.
   An inverse-patch check against main passed with a temporary index; no rollback
   was executed. Avoid rolling the whole site back to an older data bundle.
 
+## Local Typography parser backport candidate — 2026-10-23 UTC
+
+This local candidate scopes an npm override to `@tailwindcss/typography` only:
+its parser changes from 6.0.10 to **6.1.5**. Typography stays at 0.5.19; no other
+package or dependency edge changes. npm hoists the replacement from the nested
+Typography directory to `node_modules/postcss-selector-parser`. This is a local
+review candidate, not a production publication receipt.
+
+The [maintainer advisory](https://github.com/postcss/postcss-selector-parser/security/advisories/GHSA-rj75-hqrm-r3gf)
+and [6.1.5 release](https://github.com/postcss/postcss-selector-parser/releases/tag/6.1.5)
+identify the security backport for the 6.x line. The separate
+[reviewed advisory range](https://github.com/advisories/GHSA-rj75-hqrm-r3gf)
+still says `<7.1.6`, so npm may keep reporting the two moderate package entries.
+Keep those findings visible: no advisory exception, audit threshold change,
+forced downgrade, or unrelated 7.x migration is part of this candidate.
+
+The inspected consumer is the CSS build plugin in `src/index.css`, parsing
+repository sources. No browser/API import or visitor-controlled selector
+parsing endpoint was found. That limited review does not establish zero risk
+for future consumers or other dependencies.
+
+`npm run test:css-parser` resolves the parser through Typography itself, checks
+the patched version and pseudo-element transformations, and parses a flat
+400KB class/id selector in a heap-limited worker with a five-second deadline.
+The old parser fails that bounded control; the backport completes it. The test
+stops only its own worker if parsing regresses, without leaving a blocked test
+process. It is also part of the full `npm test` gate.
+
+For review or a future parent upgrade, perform a clean `npm ci`, build and full
+test suite; compare generated CSS against the same source/data input before
+the override. Recheck the actual Typography resolution and advisory metadata.
+Remove this override only when the parent itself supplies a patched compatible
+parser, then repeat the output and route checks. Preserve the existing JS/CSS
+budgets and the dated historical review below.
+
 ## Bounded dependency review — 2026-10-22 UTC
 
 Official npm audit reports **eight moderate package entries**, zero high or

package.json

@@ -5,7 +5,7 @@
   "type": "module",
   "scripts": {
     "dev": "vite",
-    "test": "npm run test:ads && npm run test:writer && npm run test:refresh && npm run test:publish && npm run test:hours && npm run test:trust && npm run test:mdx && npm run test:metadata && npm run test:audit && npm run test:bundle && npm run test:routes",
+    "test": "npm run test:ads && npm run test:writer && npm run test:refresh && npm run test:publish && npm run test:hours && npm run test:trust && npm run test:mdx && npm run test:css-parser && npm run test:metadata && npm run test:audit && npm run test:bundle && npm run test:routes",
     "test:metadata": "node --test scripts/test-faq-scope.mjs scripts/test-hreflang.mjs scripts/test-crossing-snapshot.mjs",
     "test:ads": "node --test scripts/test-ad-slot-diagnostics.mjs && node scripts/check-google-ads.mjs",
     "test:publish": "node --test scripts/test-publish-data.mjs scripts/test-public-crossings.mjs",
@@ -37,6 +37,7 @@
     "test:audit": "node scripts/check-audit.mjs",
     "test:trust": "node --test scripts/test-trust-state.mjs scripts/test-local-comparison.mjs scripts/test-browser-state.mjs scripts/test-historical-pattern.mjs scripts/test-router-navigation.mjs",
     "test:mdx": "node --test scripts/test-mdx-frontmatter.mjs",
+    "test:css-parser": "node --test scripts/test-typography-parser.mjs",
     "test:writer": "node --test scripts/test-generated-writer.mjs",
     "test:refresh": "node --test scripts/test-data-refresh.mjs"
   },
@@ -113,5 +114,10 @@
     "tailwindcss": "^4.3.3",
     "typescript": "^5.8.2",
     "vite": "^6.4.4"
+  },
+  "overrides": {
+    "@tailwindcss/typography": {
+      "postcss-selector-parser": "6.1.5"
+    }
   }
 }

scripts/test-typography-parser.mjs

@@ -0,0 +1,70 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createRequire } from 'node:module';
+import { Worker } from 'node:worker_threads';
+
+// Resolve the parser used by the CSS plugin, including a nested dependency.
+const require = createRequire(import.meta.url);
+const typographyRequire = createRequire(require.resolve('@tailwindcss/typography/package.json'));
+const parserPath = typographyRequire.resolve('postcss-selector-parser');
+const version = typographyRequire('postcss-selector-parser/package.json').version;
+const utils = typographyRequire('./src/utils.js');
+
+test('Typography resolves a version patched for GHSA-rj75-hqrm-r3gf', () => {
+  assert.match(version, /^\d+\.\d+\.\d+$/);
+  const [major, minor, patch] = version.split('.').map(Number);
+  const patched = (major === 6 && (minor > 1 || (minor === 1 && patch >= 5)))
+    || major > 7 || (major === 7 && (minor > 1 || (minor === 1 && patch >= 6)));
+  assert.ok(patched, 'Typography actually resolves vulnerable parser ' + version);
+});
+
+test('Typography preserves pseudo-element and selector-list transformations', () => {
+  const cases = [
+    ['.alpha::before', ['::before', '.alpha']],
+    ['.alpha::before, .beta::before', ['::before', '.alpha, .beta']],
+    ['.alpha:hover', [null, '.alpha:hover']],
+    ['.alpha:not(.beta)::after', ['::after', '.alpha:not(.beta)']],
+    ['[data-state="open"] > a::before', ['::before', '[data-state="open"] > a']],
+    ['section > p::before, section > a::after', [null, 'section > p::before, section > a::after']],
+  ];
+  for (const [selector, expected] of cases) {
+    assert.deepEqual(utils.commonTrailingPseudos(selector), expected);
+  }
+});
+
+test('flat class/id selectors parse within a bounded worker deadline', { timeout: 8_000 }, async t => {
+  // The advisory uses a flat 400KB selector: nesting guards cannot protect it.
+  // Bound both time and heap; a regression stops only this test's own worker.
+  const source = [
+    "const { parentPort, workerData } = require('node:worker_threads');",
+    "const { performance } = require('node:perf_hooks');",
+    'const parser = require(workerData.parserPath);',
+    "const selector = '.a#b'.repeat(100_000);",
+    'const started = performance.now();',
+    'const ast = parser().astSync(selector);',
+    'parentPort.postMessage({ nodes: ast.first.nodes.length,',
+    '  roundTrip: ast.toString() === selector, elapsedMs: performance.now() - started });',
+  ].join('\n');
+  const worker = new Worker(source, {
+    eval: true,
+    workerData: { parserPath },
+    resourceLimits: { maxOldGenerationSizeMb: 256, maxYoungGenerationSizeMb: 32 },
+  });
+  let deadline;
+  try {
+    const result = await new Promise((resolve, reject) => {
+      deadline = setTimeout(() => reject(new Error('Flat selector parsing exceeded the 5-second safety deadline')), 5_000);
+      worker.once('message', resolve);
+      worker.once('error', reject);
+      worker.once('exit', code => {
+        if (code !== 0) reject(new Error('Parser worker exited with code ' + code));
+      });
+    });
+    assert.equal(result.nodes, 200_000);
+    assert.equal(result.roundTrip, true);
+    t.diagnostic('Parser ' + version + ': 200000 selector nodes in ' + Math.round(result.elapsedMs) + 'ms');
+  } finally {
+    clearTimeout(deadline);
+    await worker.terminate();
+  }
+});