Add introductory sentence

stevepiercy · stevepiercy · commit ca037d973fa6 · 2023-03-05T23:17:29.000-08:00
diff --git a/plone.app.dexterity/index.md b/plone.app.dexterity/index.md
@@ -9,6 +9,8 @@ myst:
 
 # Content types developer manual
 
+This part of the documentation describes how to develop content types in Plone.
+
 ```{toctree}
 :maxdepth: 2
 
