diff --git a/docs/admin/config-cheat-sheet.md b/docs/admin/config-cheat-sheet.md
index f4c63d14..d1368228 100644
--- a/docs/admin/config-cheat-sheet.md
+++ b/docs/admin/config-cheat-sheet.md
@@ -638,6 +638,7 @@ And the following unique queues:
   BASIC and the user's password. Please note if you disable this you will not be able to access the
   tokens API endpoints using a password. Further, this only disables BASIC authentication using the
   password - not tokens or OAuth Basic.
+- `ENABLE_INTERNAL_SIGNIN`: **true**: Enables the builtin authentication flow. Disable this to force users to login through external authentication sources.
 - `ENABLE_REVERSE_PROXY_AUTHENTICATION`: **false**: Enable this to allow reverse proxy authentication for web requests
 - `ENABLE_REVERSE_PROXY_AUTHENTICATION_API`: **false**: Enable this to allow reverse proxy authentication for API requests, the reverse proxy is responsible for ensuring that no CSRF is possible.
 - `ENABLE_REVERSE_PROXY_AUTO_REGISTRATION`: **false**: Enable this to allow auto-registration