<p>That's odd, yes. Here's a minimal version to reproduce the issue:</p>
<pre><code>var unsafeHtml = '<div class="tooltip" role="tooltip"><div class="arrow"></div><div class="tooltip-inner"></div></div>'
var domParser = new window.DOMParser();
var createdDocument = domParser.parseFromString(unsafeHtml, 'text/html');
</code></pre>
<p>unsafeHtml happens to be the string at the place of the issue. It could be anything else, though. parseFromString will always fail.</p>

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