Merge branch '6.4' into 7.0

* 6.4:
  [Frontend] Adding info about comments

Author: javiereguiluz

frontend.rst

@@ -34,6 +34,8 @@ Supports `Stimulus/UX`_           yes                                 yes
 Supports Sass/Tailwind            :ref:`yes <asset-mapper-tailwind>`  yes
 Supports React, Vue, Svelte?      yes :ref:`[1] <ux-note-1>`          yes
 Supports TypeScript               :ref:`yes <asset-mapper-ts>`        yes
+Removes comments from JavaScript  no                                  yes
+Removes comments from CSS         no                                  no :ref:`[2] <ux-note-2>`
 Versioned assets                  always                              optional
 ================================  ==================================  ==========
 
@@ -44,6 +46,10 @@ 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.
 
+.. _ux-note-2:
+
+**[2]** There are some PostCSS plugins available to remove comments from CSS files.
+
 .. _frontend-asset-mapper:
 
 AssetMapper (Recommended)