diff --git a/README.md b/README.md
index 4d0f561..65f68d1 100644
--- a/README.md
+++ b/README.md
@@ -86,6 +86,8 @@ _Default:_ `function() return { vim.api.nvim_get_current_buf() } end`
 
 A function that specifies the buffer numbers to complete.
 
+**NOTE:** If using this, make sure you have `set hidden`, otherwise it will not work correctly.
+
 You can use the following pre-defined recipes.
 
 ##### All buffers