/usr/share/mercurial/templates/paper/graphentry.tmpl is in mercurial-common 4.5.3-1ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 | <li data-node="{node|short}">
<div class="fg">
<span class="desc">
<a href="{url|urlescape}rev/{node|short}{sessionvars%urlparameter}">{desc|strip|firstline|escape|nonempty}</a>
</span>
{alltags}
<div class="info"><span class="age">{date|rfc822date}</span>, by {author|person}</div>
</div>
</li>
|