PHP / SQL查询“删除自”在Mozilla Firefox中不起作用

Question

I have a weird issue than maybe someone had before.

I have a code to delete a row with an specific id (in my database) in a PHP file:

if(isset($_POST['delete'])){

    $bannerid = $_REQUEST['bannerid'];

    $sql = "DELETE FROM cc_homeslide WHERE id='$bannerid'";
    $conn->query($sql) === TRUE;

    echo "<script>document.location.href='home-slide.php'</script>" ;

} 

EDIT: And this is my form code

<form class='form-delete' action='home-slide-actions.php?bannerid=". $row["id"]."' method='POST'>
 <button class='delete' type='submit' name='delete'>
  <i class='fa fa-trash-o fa-2x'></i>
 </button>
</form>

This code works in Safari and Google Chrome but doesn't work in Mozilla Firefox.

Any idea bout what is going on here?