Ignore erroring modifiers when loading session

src/system/modifier-data.ts

@@ -32,6 +32,7 @@ export default class ModifierData {
     if (!typeFunc)
       return null;
 
+    try {
       let type = typeFunc();
       type.id = this.typeId;
       type.generatorId = this.typeGeneratorId;
@@ -45,5 +46,9 @@ export default class ModifierData {
         ret.stackCount = ret.getMaxStackCount(scene);
 
       return ret;
+    } catch (err) {
+      console.error(err);
+      return null;
+    }
   }
 }