diff --git a/doc/outline.txt b/doc/outline.txt
index f4d2ef0..7040bdb 100644
--- a/doc/outline.txt
+++ b/doc/outline.txt
@@ -19,7 +19,7 @@ Table of Contents                                  *outline-table-of-contents*
 PREREQUISITES                                          *outline-prerequisites*
 
 - Neovim 0.7+
-- Properly configured Neovim LSP client
+- Properly configured Neovim LSP client (otherwise only markdown is supported)
 
 
 INSTALLATION                                            *outline-installation*