diff --git a/changelog.d/13665.doc b/changelog.d/13665.doc
new file mode 100644
index 0000000000000000000000000000000000000000..6ee6434662f7cfe7b9bf397918e8e0a67b4dc36a
--- /dev/null
+++ b/changelog.d/13665.doc
@@ -0,0 +1 @@
+Remove unintentional colons from [config manual](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html) headers.
diff --git a/docs/usage/configuration/config_documentation.md b/docs/usage/configuration/config_documentation.md
index 88e8e1c66f0000ba1867685780f596637870a3cf..396c56082252c00c7c0db2a5b3858992a1c2d1cf 100644
--- a/docs/usage/configuration/config_documentation.md
+++ b/docs/usage/configuration/config_documentation.md
@@ -2486,7 +2486,7 @@ report_stats_endpoint: https://example.com/report-usage-stats/push
 Config settings related to the client/server API
 
 ---
-### `room_prejoin_state:`
+### `room_prejoin_state`
 
 Controls for the state that is shared with users who receive an invite
 to a room. By default, the following state event types are shared with users who
@@ -2626,7 +2626,7 @@ Example configuration:
 key_refresh_interval: 2d
 ```
 ---
-### `trusted_key_servers:`
+### `trusted_key_servers`
 
 The trusted servers to download signing keys from.