javascript - Lawnchair コードが 2 回実行される

Question

I am trying to use Lawnchair and have found that it seems to execute all functions twice. This may be just something I am doing wrong with JavaScript in general. Here is and example that does nothing other than demonstrate my problem.

console.log("Flag 1");

Lawnchair(function() {
    console.log("Flag 2");
});

In this example the console shows this.

Flag 1
Flag 2
Flag 2

So while the whole section of code is only getting called once, the inner function is indeed getting called twice.

Is this a syntax problem?