<base> is currently limited to one appearance per html document, and must appear in the <head>. Why this limitation?
I would be convenient, for instance, to be able to make an index in the following form:
<base href=“http://xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
<ul>
<li><a href="#1"> 22.1 Global Heating</a></li>
<li><a href="#2"> 22.2 Vostok Data</a></li>
<li><a href="#3"> 22.3 Early Methane</a></li>
...
</ul></base>
<base href=“http://yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy">
<ul>
<li><a href=“#1"> 23.1 Antarctic Ice Loss</a></li>
<li><a href=“#2"> 23.2 Arctic Ice Loss</a></li>
<li><a href=“#3"> 23.3 25-Year Model</a></li>
…
</ul></base>
It would save a lot of writing!