diff --git a/mrs.developer.json b/mrs.developer.json
index 9f9809d9..19c0f80c 100644
--- a/mrs.developer.json
+++ b/mrs.developer.json
@@ -1,7 +1,8 @@
 {
   "volto-mosaic": {
     "url": "https://github.com/eea/volto-mosaic.git",
-    "path": "src"
+    "path": "src",
+    "branch": "blocks_override"
   },
   "volto-datablocks": {
     "url": "https://github.com/eea/volto-datablocks.git",