diff --git a/README.rst b/README.rst
index c3f03d43..7d20a29d 100644
--- a/README.rst
+++ b/README.rst
@@ -71,6 +71,7 @@ Compatibility
 =============
 
 Add-on's created with ``bobtemplates.plone`` are tested to work in **Plone >= 5.2** and **Python >= 3.7**.
+the only exceptions are the theming templates. Those are Plone 6 only, because the markup and Diazo rules have changed.
 
 If you need to create Plone packages for older versions of Plone and Python, please use bobtemplates.plone 5.x.
 It should work on Linux, Mac and Windows.