提交按钮不在Chrome中工作但在Firefox中工作

Hi the logout button is not working in chrome. It is working fine in Firefox. However if I press F12 and keep the developer console open then the button works. The button also works when I press enter. I'm confused. Here is my code.

HTML Code:

<form name="logoutform" method="post" onsubmit="logoutConfirmation()" action="" >
        <input type="submit" value="Logout" id="logoutbutton" name="userlogout" ><br>
    </form>

JS Code:

function logoutConfirmation()
 {
alert("Thank you. Have a nice day!");
 }

PHP Code:

if(isset($_POST['userlogout']))
    {
        setcookie('user_name', '');
        setcookie('user_id', '');
        session_destroy();
        header("Location: index.php");
    }

Define the action php file in your form like;

<form name="logoutform" method="post" onsubmit="logoutConfirmation()" action="yourfile.php" >
        <input type="submit" value="Logout" id="logoutbutton" name="userlogout" ><br>
</form>

If you don't set action. It's not submitted.

Try something like this if your file is named "test.php":

<?php
echo <<<STR
<html>
<head>
<script>
// your script
</script>
</head>
<body>
<form method="post" name="logoutForm" onsubmit="logoutConfirmation();" action="test.php">
    <input type="submit" name="userlogout" value="Logout" id="logoutButton">
</form>
</body>
</html>
STR;
?>

If the PHP script is in the same file then you don't even need action="".

Just do this:

<form name="logoutform" method="post" onsubmit="logoutConfirmation()">
    <input type="submit" value="Logout" id="logoutbutton" name="userlogout" ><br>
</form>