Merge branch '6.3' into 6.4

* 6.3:
  Replace footnote by ref

Author: javiereguiluz

frontend.rst

@@ -25,8 +25,8 @@ Requires a build step?            yes                no
 Works in all browsers?            yes                yes
 Supports `Stimulus/UX`_           yes                yes
 Supports Sass/Tailwind            yes                :ref:`yes <asset-mapper-tailwind>`
-Supports React, Vue, Svelte?      yes                yes (but read note below)
-Supports TypeScript               yes                no (but read note below)
+Supports React, Vue, Svelte?      yes                yes :ref:`[1] <note-1>`
+Supports TypeScript               yes                no :ref:`[1] <note-1>`
 ================================  =================  ======================================================
 
 .. note::
@@ -36,6 +36,16 @@ Supports TypeScript               yes                no (but read note below)
     Vue single-file components) cannot be compiled down to pure JavaScript that can
     be executed by a browser.
 
+Notes
+~~~~~
+
+.. _note-1:
+
+**[1]** Using JSX (React), Vue or TypeScript with AssetMapper is possible, but you'll
+need to use their native tools for pre-compilation. Also, some features (like
+Vue single-file components) cannot be compiled down to pure JavaScript that can
+be executed by a browser.
+
 .. _frontend-webpack-encore:
 
 Webpack Encore