Ajax PHP - 仅当 DOM Explorer 打开 (Edge） 时，才会回显结果

我有一个页面，它每 4 秒使用 Ajax 调用一次 PHP 脚本。PHP 脚本回显出一些文本，然后将其放入页面上的div 中。（PHP脚本确实连接到MySQL服务器，这可能是我下面问题的原因吗？

这是奇怪的部分。第一次调用 PHP 脚本时，它会很好地回显所有文本。但是，4 秒后，当 Ajax 再次调用 PHP 脚本时，页面变为空白。更奇怪的是，当我右键单击MS Edge上的"查看源代码"时，所有页面内容都会加载，然后如果我关闭源代码，则在4秒后它再次消失。

有谁知道为什么会这样？

我使用 Ajax 的 JS 文件：

function updateCandles(){
    var candleIndexStart = $('#candle-index-start').text();
    var candleSort = $('#candle-sort').text();
    var resultArray = $.ajax({
        type: 'GET',
        url: 'php/display_candles.php',
        data: {
            'sort': candleSort,
            'candle-start': candleIndexStart
        },
        async: false
    }).responseText.split("h8ktncuidabciafvabc7932hcueqbc73gd8713gdy713gd6831df8136fd13d");
    $('.candles').html(resultArray[0]);
    $('#candle-counter').html(resultArray[1]);
    setTimeout(updateCandles, 4000);
}
$(document).ready(function(){
    updateCandles();
});

我的PHP脚本：

<?php
session_start();
function timeAgo($time_ago)
{
    $time_ago = strtotime($time_ago);
    $cur_time   = time();
    $time_elapsed   = $cur_time - $time_ago;
    $seconds    = $time_elapsed ;
    $minutes    = round($time_elapsed / 60 );
    $hours      = round($time_elapsed / 3600);
    $days       = round($time_elapsed / 86400 );
    $weeks      = round($time_elapsed / 604800);
    $months     = round($time_elapsed / 2600640 );
    $years      = round($time_elapsed / 31207680 );
    // Seconds
    if($seconds <= 60){
        return "just now";
    }
    //Minutes
    else if($minutes <=60){
        if($minutes==1){
            return "one minute ago";
        }
        else{
            return "$minutes minutes ago";
        }
    }
    //Hours
    else if($hours <=24){
        if($hours==1){
            return "an hour ago";
        }else{
            return "$hours hrs ago";
        }
    }
    //Days
    else if($days <= 7){
        if($days==1){
            return "yesterday";
        }else{
            return "$days days ago";
        }
    }
    //Weeks
    else if($weeks <= 4.3){
        if($weeks==1){
            return "a week ago";
        }else{
            return "$weeks weeks ago";
        }
    }
    //Months
    else if($months <=12){
        if($months==1){
            return "a month ago";
        }else{
            return "$months months ago";
        }
    }
    //Years
    else{
        if($years==1){
            return "one year ago";
        }else{
            return "$years years ago";
        }
    }
}
$connection = mysqli_connect("localhost", "username", "pass", "db");
if(!$connection) {
    echo "Error";
}
if($_GET['teacher'] == 'yes'){
    $result2 = mysqli_query($connection, "SELECT * FROM candles WHERE approved=0 ORDER BY date desc LIMIT " . $_GET['candle-start'] . ",20");
} else {
    $result2 = mysqli_query($connection, "SELECT * FROM candles WHERE approved=1 ORDER BY date " . $_GET['sort'] . " LIMIT " . $_GET['candle-start'] . ",20");
}
if(mysqli_num_rows($result2) > 0) {
    $counter = 0;
    while($row = mysqli_fetch_assoc($result2)) {
        $counter = $counter + 1;
        if($counter % 2 == 1){
            echo "</div>";
            echo "<div class='candle-row'>";
        }
        if($row["approved"] == 1 and $_GET['teacher'] == 'yes') {
            continue;
        }
        echo "<div class='candle'><div class='candle-icon'>";
        echo '<span class="fa-stack fa-4x"><i class="fa fa-square-o fa-stack-2x"></i><i class="fa fa-' . $row["candle_icon_type"] . ' fa-stack-1x" style="color: ' . $row["colour"] . '"></i></span></div>';
        echo '<div style="display:table;height:100%;"><div style="display:table-cell;vertical-align:middle;"><div>';
        echo "<h3><a href='candle.php?id=" . $row["id"] . "'>For " . ucwords($row["title"]) . "</a></h3>";
        echo "<br>";
        $result3 = mysqli_query($connection, "SELECT * FROM users WHERE id=" . $row['user_id'] . " LIMIT 1");
        if(mysqli_num_rows($result3) > 0) {
            while($row1 = mysqli_fetch_assoc($result3)) {
                if($row["anonymous"] == 1 and $_SESSION["user_group"] == '1'){
                    echo "<h4><a href='candle.php?id=" . $row["id"] . "'>Shared by an Anonymous User<br>";
                } else {
                    echo "<h4><a href='candle.php?id=" . $row["id"] . "'>Shared by " . $row1["username"] . "<br>";
                }
            }
        } else {
            echo "<h4><a href='candle.php?id=" . $row["id"] . "'>Shared by Unknown<br>";
        }
        echo "Shared " . ucwords(timeAgo($row["date"])) . "<br>" . $row['fuel'] . " Fuel</a></h4></div></div></div>";
        echo "</div>";
    }
}
echo "h8ktncuidabciafvabc7932hcueqbc73gd8713gdy713gd6831df8136fd13d";
if($_GET['teacher']) {
    $result1 = mysqli_query($connection, "SELECT id FROM candles WHERE approved=0");
} else {
    $result1 = mysqli_query($connection, "SELECT id FROM candles WHERE approved=1");
}
if(mysqli_num_rows($result1) == 0){
    echo '0 Candles';
} elseif(mysqli_num_rows($result1) == 1){
    echo '1 Candle';
} else {
    echo mysqli_num_rows($result1) . ' Candles';
}
mysqli_close($connection);
?>