diff -u b/core/package.json b/core/package.json
--- b/core/package.json
+++ b/core/package.json
@@ -29,7 +29,7 @@
           "targets": {
             "browsers": [
               "last 2 versions",
-              "ie >= 11"
+              "ie >= 9"
             ]
           }
         }