diff --git a/public/docs/features.md b/public/docs/features.md
index c2896952..d99dbffb 100644
--- a/public/docs/features.md
+++ b/public/docs/features.md
@@ -334,6 +334,9 @@ gantt
 
 More information about **mermaid** syntax [here](https://mermaid-js.github.io/mermaid/)
 
+This version of HedgeDoc bundles Mermaid 9.1.7. The documentation for this version can
+be found [here](https://github.com/mermaid-js/mermaid/blob/v9.1.7/docs/n00b-gettingStarted.md).
+
 #### Abc Music Notation
 
 ```abc
diff --git a/public/docs/release-notes.md b/public/docs/release-notes.md
index f06eebb1..79c0d68f 100644
--- a/public/docs/release-notes.md
+++ b/public/docs/release-notes.md
@@ -1,5 +1,10 @@
 # Release Notes
 
+## UNRELEASED
+
+### Enhancements
+- Add a pointer to Mermaid 9.1.7 documentation, which is what HedgeDoc 1 supports.
+
 ## <i class="fa fa-tag"></i> 1.9.9 <i class="fa fa-calendar-o"></i> 2023-07-30
 
 HedgeDoc has a new slogan! See [our announcement](https://community.hedgedoc.org/t/and-the-new-slogan-is/) for the details.