diff --git a/pkgs/development/libraries/webkit/default.nix b/pkgs/development/libraries/webkit/default.nix
index 8865c2fb6bf3..e280a70a6e08 100644
--- a/pkgs/development/libraries/webkit/default.nix
+++ b/pkgs/development/libraries/webkit/default.nix
@@ -18,6 +18,8 @@ rec {
     "--enable-3D-transforms"
     "--enable-filters"
     "--enable-web-sockets"
+    "--enable-shared-workers"
+    "--enable-wml"
     ];
 
   /* doConfigure should be specified separately */