--- a/net/minecraft/client/main/Main.java
+++ b/net/minecraft/client/main/Main.java
@@ -120,7 +120,7 @@
       String s7 = func_206236_a(optionset, optionspec);
       Integer integer = func_206236_a(optionset, optionspec1);
       CrashReport.func_230188_h_();
-      Bootstrap.func_151354_b();
+      net.minecraftforge.fml.loading.BackgroundWaiter.runAndTick(()->Bootstrap.func_151354_b(), net.minecraftforge.fml.loading.FMLLoader.progressWindowTick);
       Bootstrap.func_218821_c();
       Util.func_240994_l_();
       Session session = new Session(optionspec10.value(optionset), s5, optionspec12.value(optionset), optionspec21.value(optionset));
