不知道他们为什么这样做，但是，你可以通过重置页面顶部的哈希来解决这个问题:

if (window.location.hash == "#_=_")
  window.location.hash = "";

你也可以在Facebook回调的redirect_uri参数上指定你自己的散列，这在某些情况下可能是有帮助的，例如/api/account/callback#home。当你被重定向回来，它至少是一个哈希，对应于一个已知的路由，如果你使用backbone.js或类似的(不确定jquery移动)。

使用angular和angular ui router，你可以修复这个问题

    app.config(function ($stateProvider, $urlRouterProvider, $locationProvider) {

      // Make a trailing slash optional for all routes
      // - Note: You'll need to specify all urls with a trailing slash if you use this method.
      $urlRouterProvider.rule(function ($injector, $location) {
        /***
        Angular misbehaves when the URL contains a "#_=_" hash.

        From Facebook:
          Change in Session Redirect Behavior
          This week, we started adding a fragment #_=_ to the redirect_uri when this field is left blank.
          Please ensure that your app can handle this behavior.

        Fix:
          http://stackoverflow.com/questions/7131909/facebook-callback-appends-to-return-url#answer-7297873
        ***/
        if ($location.hash() === '_=_'){
          $location.hash(null);
        }

        var path = $location.url();

        // check to see if the path already has a slash where it should be
        if (path[path.length - 1] === '/' || path.indexOf('/?') > -1) {
          return;
        }
        else if (path.indexOf('?') > -1) {
          $location.replace().path(path.replace('?', '/?'));
        }
        else {
          $location.replace().path(path + '/');
        }
      });

      // etc ...
    });
});

对于那些正在寻找简单答案的人 加上这个，对我很管用

if (window.location.hash === "#_=_"){
    history.replaceState 
        ? history.replaceState(null, null, window.location.href.split("#")[0])
        : window.location.hash = "";
}

请查看Paul Schwarz的完整回答

https://stackoverflow.com/a/18305085/2694806

我使用这个，删除'#'符号。

<script type="text/javascript">
    if (window.location.hash && window.location.hash == '#_=_') {
        window.location.href = window.location.href.split('#_=_')[0];
    }
</script>

博士TL;

if (window.location.hash === "#_=_"){
    history.replaceState 
        ? history.replaceState(null, null, window.location.href.split("#")[0])
        : window.location.hash = "";
}

完整版本与一步一步的说明

// Test for the ugliness.
if (window.location.hash === "#_=_"){

    // Check if the browser supports history.replaceState.
    if (history.replaceState) {

        // Keep the exact URL up to the hash.
        var cleanHref = window.location.href.split("#")[0];

        // Replace the URL in the address bar without messing with the back button.
        history.replaceState(null, null, cleanHref);

    } else {

        // Well, you're on an old browser, we can get rid of the _=_ but not the #.
        window.location.hash = "";

    }

}

循序渐进:

We'll only get into the code block if the fragment is #_=_. Check if the browser supports the HTML5 window.replaceState method. Clean the URL by splitting on # and taking only the first part. Tell history to replace the current page state with the clean URL. This modifies the current history entry instead of creating a new one. What this means is the back and forward buttons will work just the way you want. ;-) If the browser does not support the awesome HTML 5 history methods then just clean up the URL as best you can by setting the hash to empty string. This is a poor fallback because it still leaves a trailing hash (example.com/#) and also it adds a history entry, so the back button will take you back to #_-_.

了解更多关于历史的知识。

了解window.location的更多信息。