$def with ()
$var title: Cache

<form method=post style="margin:3em 0">
<label style=font-size:.9em><strong>Address</strong>
<small><em>i.e. website URL or fediverse handle</em></small><br>
<input style="border:.2em inset #ccc;border-radius:.2em;font-size:1.1em;margin:.25em 0 .5em 0;padding:.2em;width:calc(100% - .8em)"
name=address type=text autofocus placeholder="e.g. example.com or alice@example.com"></label>
<div style=text-align:right><button
style="font-size:.8em;padding:0 .2em;text-transform:uppercase">Validate</button></div>
</form>

<h2 id=standards>Supported Standards</h2>

<h3>IndieWeb</h3>

<ul style=columns:3>
<li><a href=https://www.w3.org/TR/webmention>Webmention</a></li>
<li><a href=https://www.w3.org/TR/websub>WebSub</a></li>
<li><a href=https://www.w3.org/TR/indieauth>IndieAuth</a></li>
<li><a href=https://indieweb.org/Ticketing_for_IndieAuth>Ticketing</a></li>
<li><a href=https://www.w3.org/TR/micropub>Micropub</a></li>
<li><a href=https://indieweb.org/Microsub>Microsub</a></li>
<li><a href=https://microformats.org/wiki/microformats>microformats</a></li>
<li><a href=https://microformats.org/wiki/metaformats>metaformats</a></li>
<li><a href=https://www.w3.org/TR/post-type-discovery><abbr title="Post Type Discovery">PTD</abbr></a></li>
<li><a href=https://gmpg.org/xfn/><abbr title="XHTML Friends Network">XFN</abbr></a></li>
<li><a href=https://microformats.org/wiki/rel-me>rel=me</a></li>
<li><a href=https://microformats.org/wiki/web-sign-in>web sign in</a></li>
<li><a href=https://www.w3.org/TR/jf2>JF2</a></li>
</ul>

<h3>Complimentary</h3>

<ul style=columns:3>
<li><a href=https://cyber.harvard.edu/rss/rss.html>RSS</a></li>
<li><a href=https://datatracker.ietf.org/doc/html/rfc4287>Atom Syndication Format</a></li>
<li><a href=https://www.jsonfeed.org/version/1.1>JSON Feed</a></li>
<li><a href=https://datatracker.ietf.org/doc/html/rfc6415>Web Host Metadata</a></li>
<li><a href=http://nodeinfo.diaspora.software/protocol.html>NodeInfo</a></li>
<li><a href=https://datatracker.ietf.org/doc/html/rfc7033>WebFinger</a></li>
<li><a href=https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-message-signatures>HTTP Signatures</a></li>
<li><a href=https://www.w3.org/TR/activitypub>ActivityPub</a></li>
<li><a href=https://www.w3.org/TR/activitystreams-vocabulary>Activity Vocabulary</a></li>
<li><a href=https://datatracker.ietf.org/doc/html/rfc6797><abbr title="HTTP Strict Transport Security">HSTS</abbr></a></li>
</ul>