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<html><head><script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script><script>$(document).ready(function(){ $("input").blur(function(){ alert("This input field has lost its focus."); });});</script></head><body>Enter your name: <input type="text"><p>Write something in the input field, and then click outside the field to lose focus (blur).</p></body></html>