1 files changed, 6 insertions, 0 deletions
diff --git a/gui.js b/gui.js
index 6af9137..9d6d952 100644
--- a/gui.js
+++ b/gui.js
@@ -3440,6 +3440,12 @@ IDE_Morph.prototype.reflectLanguage = function (lang, callback) {
             projectData = this.serializer.serialize(this.stage);
         }
     }
+    this.world().children.forEach(function (morph) {
+        if (morph instanceof BlockEditorMorph) {
+            morph.updateDefinition(); // save custom blocks
+            // otherwise, initBlocks() will reset the definition
+        }
+    });
     SpriteMorph.prototype.initBlocks();
     this.spriteBar.tabBar.tabTo('scripts');
     this.createCategories();