Added support for old format.

src/config.ts

@@ -149,6 +149,15 @@ function decodeStoredItem(id: string, data) {
         }
     }
 
+    // This is the old format for SBMap (a JSON string)
+    if (typeof data === "string") {
+        let str = JSON.parse(data);	   
+
+        if(Array.isArray(data)) {
+            return new SBMap(id, str)
+        }
+    }
+    
     // If all else fails, return the data
     return data;
 }