You can't disable your limit framerate hook according to your mixin it's always going to be a configurable option instead of vanilla. This means your directly incompatible with Custom Main Menu Mod and Menu Lib mod. As you can see below if it's synced do your thing else also do your thing just a static value. This means your overriding everyone else.

   @Inject(
      method = {"getLimitFramerate"},
      cancellable = true,
      at = {@At("HEAD")}
   )
   public void getLimitFramerate(CallbackInfoReturnable info) {
      if (this.field_71441_e == null) {
         if (RenderLibConfig.mainMenuFPSSynced) {
            info.setReturnValue(MathHelper.func_76125_a(this.field_71474_y.field_74350_i, 30, 240));
         } else {
            info.setReturnValue(RenderLibConfig.mainMenuFPS);
         }
      } else {
         info.setReturnValue(this.field_71474_y.field_74350_i);
      }

   }

I don't see anything in CustomMainMenu that messes with the FPS limit. Am I missing something?

MenuLib compatibility will be added with the next release.

I don't see anything in CustomMainMenu that messes with the FPS limit. Am I missing something?

MenuLib compatibility will be added with the next release.

I thought they also had a frame limit override I guess not? Anyways incompat with MenuLib