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# Error: error:btstrpd
App Already Bootstrapped with this Element

    App Already Bootstrapped with this Element '{0}'

## Description

Occurs when calling `angular.bootstrap` on an element that has already been bootstrapped.

This usually happens when you accidentally use both `ng-app` and `angular.bootstrap` to bootstrap an application.

    <html>
    ...
      <body ng-app="myApp">
        <script>
          angular.bootstrap(document.body, ['myApp']);
        </script>
      </body>
    </html>

Note that for bootstrapping purposes, the `<html>` element is the same as `document`, so the following will also throw an error.

    <html>
    ...
    <script>
      angular.bootstrap(document, ['myApp']);
    </script>
    </html>

You can also get this error if you accidentally load AngularJS itself more than once.

    <html ng-app>
    <head>
      <script src="angular.js"></script>

      ...

    </head>
    <body>

      ...

      <script src="angular.js"></script>
    </body>
    </html>