diff --git a/css/properties/background-position-x.json b/css/properties/background-position-x.json
index e6ac558a0389ba..574911612b3f65 100644
--- a/css/properties/background-position-x.json
+++ b/css/properties/background-position-x.json
@@ -22,9 +22,7 @@
             },
             "oculus": "mirror",
             "opera": "mirror",
-            "opera_android": {
-              "version_added": "18"
-            },
+            "opera_android": "mirror",
             "safari": {
               "version_added": "1"
             },