Add main index.html as 404.html

.github/workflows/build.yml

@@ -20,6 +20,9 @@ jobs:
         npm install
         npm run build
 
+    - name: Redirect 404 to Index for SPA
+      run: cp dist/index.html dist/404.html
+
     - name: Deploy
       uses: peaceiris/actions-gh-pages@v3
       with:

src/404.html

@@ -1,6 +0,0 @@
-<script>
-  // Disabled until santization is verified.
-  //   const path = window.location.pathname.slice(1);
-  //   localStorage.setItem("path", path);
-  window.location.href = "../";
-</script>