novitocnaforume,
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<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title>ГГ</title>
<style>
.container>span {
color: red;
}
</style>
</head>
<body>
<div class="container">
Этот текст
<span>как всегда</span>
ни о <span>чём</span>
</div>
<button>Жми</button>
<script>
document.querySelector("button").onclick = function() {
[].forEach.call(document.querySelectorAll(".container>span"), function(a) {
for (var b = a.parentNode, c; c = a.childNodes[0];) b.insertBefore(c, a);
b.removeChild(a)
})
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</body>
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