NV doesn't like file:/// links with url encoded square brackets [ ]
Code:
<div>
<p><a href="file:///D:/Calibre/Libraries/Default/!Attachments/book%20%5B30%5D/"><span style="color: #9e7852">book [30]</span></a></p>
<p><a href="file:///D:/Calibre/Libraries/Default/!Attachments/book%20(30)"><span style="color: #9e7852">book (30)</span></a></p>
<p><a href="file:///D:/Calibre/Libraries/Default/!Attachments/book%2030/"><span style="color: #9e7852">book 30</span></a></p></div>
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