diff --git a/scripts/generate_site.py b/scripts/generate_site.py
index 68898f68..48f8a4c0 100644
--- a/scripts/generate_site.py
+++ b/scripts/generate_site.py
@@ -4116,6 +4116,22 @@ def _build_emulator_file_index(profiles: dict) -> dict[str, dict]:
     }
 
 
+def _mkdocs_config(docs: Path, text: str) -> tuple[Path, str]:
+    """Where the site's config goes, and its text for that place.
+
+    The tracked mkdocs.yml belongs to docs/. A preview into another folder
+    rewrote it anyway, with the navigation of work in progress, and mkdocs
+    kept reading docs/. Another folder gets its own config beside it, its
+    paths taken from there.
+    """
+    if os.path.normpath(str(docs)) == DOCS_DIR:
+        return Path("mkdocs.yml"), text
+    where = docs.parent
+    for relative in ("scripts/mkdocs_hooks.py", "docs_assets/overrides"):
+        text = text.replace(relative, os.path.relpath(relative, where).replace(os.sep, "/"))
+    return where / f"{docs.name}.mkdocs.yml", f"docs_dir: {docs.name}\n" + text
+
+
 # mkdocs.yml nav generator
 
 
@@ -4752,7 +4768,8 @@ validation:
   unrecognized_links: warn
   anchors: warn
 """
-    write_if_changed("mkdocs.yml", mkdocs_static + nav_yaml)
+    config_path, config_text = _mkdocs_config(Path(docs), mkdocs_static + nav_yaml)
+    write_if_changed(str(config_path), config_text)
 
     total_pages = (
         1  # home
diff --git a/tests/test_site_validation.py b/tests/test_site_validation.py
index 9f75980b..65733f59 100644
--- a/tests/test_site_validation.py
+++ b/tests/test_site_validation.py
@@ -306,5 +306,19 @@ class PlainHouseStyle(unittest.TestCase):
                 self.assertFalse(first.endswith(" - RetroBIOS"), first)
 
 
+class APreviewLeavesTheTrackedConfig(unittest.TestCase):
+    """--docs-dir moved the pages but still rewrote the tracked mkdocs.yml."""
+
+    def test_another_folder_gets_its_own_config(self):
+        from generate_site import _mkdocs_config
+
+        path, text = _mkdocs_config(Path("docs"), "hooks:\n  - scripts/mkdocs_hooks.py\n")
+        self.assertEqual(path, Path("mkdocs.yml"))
+        path, text = _mkdocs_config(Path("tmp/preview"), "hooks:\n  - scripts/mkdocs_hooks.py\n")
+        self.assertEqual(path, Path("tmp/preview.mkdocs.yml"))
+        self.assertTrue(text.startswith("docs_dir: preview\n"))
+        self.assertIn("../scripts/mkdocs_hooks.py", text)
+
+
 if __name__ == "__main__":
     unittest.main()