diff --git a/Filter-syntax-extensions.md b/Filter-syntax-extensions.md
index 9604ad4..f6550c7 100644
--- a/Filter-syntax-extensions.md
+++ b/Filter-syntax-extensions.md
@@ -2,7 +2,7 @@ uBlock supports most of [Adblock Plus filter syntax](https://adblockplus.org/en/
 
 ### Not supported		
 
-`document`:
+`document` for exception filters (those prefixed with `@@`):
 
 Not supported. The purpose of the `document` option is to disable uBlock completely. The reason it is not supported is to be sure that users explicitly disable uBlock themselves if they wish (through [whitelisting](https://github.com/gorhill/uBlock/wiki/How-to-whitelist-a-web-site)), not having some external filter list decide for them.
 
@@ -12,6 +12,10 @@ uBlock extends Adblock Plus filter syntax.
 
 #### Network filters
 
+`document` for block filters:
+
+This will cause web pages which match the filter to be subjected to strict blocking.
+
 `important`:
 
 The filter option `important` means to ignore all _exception_ filters (those prefixed with `@@`).