bug symfony#8375 add empty h1 tags to html template (ArlingtonHouse, weaverryan)

This PR was merged into the 3.3 branch.

Discussion
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add empty h1 tags to html template

First Example tutorial needs the tag in order to work.

Commits
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e7642f7 removing h1 but making JS more fool-proof
3a97249 add empty h1 tags to html template

Author: weaverryan

frontend/encore/simple-example.rst

@@ -144,7 +144,7 @@ Great! Use ``require()`` to import ``jquery`` and ``greet.js``:
     var greet = require('./greet');
 
     $(document).ready(function() {
-        $('h1').html(greet('john'));
+        $('body').prepend('<h1>'+greet('john')+'</h1>');
     });
 
 That's it! When you build your assets, jQuery and ``greet.js`` will automatically