Use .x.

whatthejeff · whatthejeff · commit 13ae99d622b8 · 2013-06-22T21:50:31.000-04:00
diff --git a/composer.json b/composer.json
@@ -40,7 +40,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "1.2-dev"
+            "dev-master": "1.2.x-dev"
         }
     },
     "include-path": [
