[Docs, usernmanual] Fix with-icu=builtin explanation
diff --git a/docs/usermanual-integration.xml b/docs/usermanual-integration.xml
index 5f922ab..78c9a0e 100644
--- a/docs/usermanual-integration.xml
+++ b/docs/usermanual-integration.xml
@@ -550,11 +550,15 @@
to a <type>hb_script_t</type>.
</para>
<para>
- By default, ICU support is included when compiling HarfBuzz from
- source. The build system will look for the ICU library and link
- to it if it is found. You can also build HarfBuzz with it own,
- internal copy of ICU, by specifying the
- <literal>--with-icu=builtin</literal> compile-time option.
+ By default, HarfBuzz's ICU support is built as a separate shared
+ library (<filename class="libraryfile">libharfbuzz-icu.so</filename>)
+ when compiling HarfBuzz from source. This allows client programs
+ that do not need ICU to link against HarfBuzz without unnecessarily
+ adding ICU as a dependency. You can also build HarfBuzz with ICU
+ support built directly into the main HarfBuzz shared library
+ (<filename class="libraryfile">libharfbuzz.so</filename>),
+ by specifying the <literal>--with-icu=builtin</literal>
+ compile-time option.
</para>
</section>
