diff --git a/.hgtags b/.hgtags
index 122666825a..c45d30531c 100644
--- a/.hgtags
+++ b/.hgtags
@@ -10,3 +10,4 @@ fc827a8182eeabea27b4107630814f58615a5093 5.4.0
 4d757048f5cf112af97613ed3cd8c1d9747d5932 6.0.0
 0f981b2c2095bb4284ed6e1abe9e5f076e44bc65 6.2.0
 656bbe82f32db7cc41ba407bb46eb8ef4d78b72d 6.4.0
+81a891f156685cf5afe526044217c806990d462b 6.6.0