DOC-3526: Chat can now update an empty document (#4214)

* DOC-3526: Add TinyMCE AI bug fix release note for chat updating empty documents (TINY-14393)

* Docs: DOC-3526 - Improve TINY-14393 release note body structure

* Docs: DOC-3526 - Refine TINY-14393 release note wording per style review

* Update modules/ROOT/pages/8.7.0-release-notes.adoc

Co-authored-by: Kim <45845989+kimwoodfield@users.noreply.github.com>

---------

Co-authored-by: Kim <45845989+kimwoodfield@users.noreply.github.com>

Author: kemister85

modules/ROOT/pages/8.7.0-release-notes.adoc

@@ -28,6 +28,21 @@ include::partial$misc/admon-releasenotes-for-stable.adoc[]
 
 The following premium plugin updates were released alongside {productname} {release-version}.
 
+=== TinyMCE AI
+
+The {productname} {release-version} release includes an accompanying release of the **TinyMCE AI** premium plugin.
+
+**TinyMCE AI** includes the following fix.
+
+==== Chat can now update an empty document
+// #TINY-14393
+
+Previously, Chat did not update an empty document when generating content. Chat displayed the generated content only in the Chat sidebar, because the AI service could not apply edits when the document had no content.
+
+In {productname} {release-version}, AI Chat can now handle updating an empty document. When the editor is empty, the generated content is now directly inserted into the document rather than only being displayed in the sidebar.
+
+For information on the **TinyMCE AI** plugin, see: xref:tinymceai.adoc[TinyMCE AI].
+
 // === <Premium plugin name 1> <Premium plugin name 1 version>
 
 // The {productname} {release-version} release includes an accompanying release of the **<Premium plugin name 1>** premium plugin.