diff --git a/runtime/doc/various.txt b/runtime/doc/various.txt
index 8f3d946..2c9f8b2 100644
--- a/runtime/doc/various.txt
+++ b/runtime/doc/various.txt
@@ -575,6 +575,8 @@
 			   |:marks|      - filter by text in the current file,
 					   or file name for other files
 			   |:oldfiles|   - filter by file name
+			   |:registers|  - filter by register contents
+					   (does not work multi-line)
 			   |:set|        - filter by variable name
 
 			Only normal messages are filtered, error messages are