diff --git a/sites/github.styl b/sites/github.styl
index 585a390..ebba045 100644
--- a/sites/github.styl
+++ b/sites/github.styl
@@ -167,6 +167,10 @@ a.filter-item
 .text-diff-deleted
     color red
 
+.avatar
+.timeline-comment-avatar
+    filter opacity(50%)
+
 // ** Code syntax highlighting
 .blob-code
     background-color()