Externalize #regex block in query.html.
Fixes
RELNOTES:
@@ -1513,6 +1513,12 @@ maxrank
</p>
+<h3 id="regex">Regular expressions</h3>
+
+Regular expressions in the query language are implemented using the Java
+regex library, so they support the full syntax documented
+for <a href="https://docs.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html"><code>java.util.regex.Pattern</code></a>.
+
<h3 id="external-repos">Querying with external repositories</h3>
<p>
