index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .container { background: #CCC; }

        .block {
            position: relative;
            width: 100px;
            height: 100px;
            background: #888;
            border-radius: 33%;
            color: white;
            font-size: 10px;
        }

        .container {
            padding: 15px;
        }

        .block-child {
            position: absolute;
            left: 70px;
            top: 20px;
            width: 50px;
            height: 50px;
            background: #333;
            border-radius: 33%;
        }
    </style>
</head>
<body>
    Source:
    <div class="container">
    <div id="source" class="block">
        T説🧜pѬѬasѪ"§§)("!编/)$=?!°&%)?§"$(§sw汉字编码§"$(§sw汉字方法orФdpѬѬasѪ"§§)("!/)$=?!°&%)?编码方法orФd
        <div class="block-child"></div>
    </div>
    </div>

    Target (Copy without child and overloaded style):
    <div class="container">
        <img id="target"/>
    </div>
    <script type="module">
        import nodeToDataURL from './src/index.ts'
        
        const visualSource = document.getElementById('source')
        const imageTarget = document.getElementById('target')
        const excluded = document.querySelectorAll('.block-child')

        nodeToDataURL({
            targetNode: visualSource,
            excludedNodes: excluded,
            customStyle: '.block { background: red; }'
        })
        .then((url) => {
            imageTarget.setAttribute('src', url);
        })
    </script>
</body>
</html>