Minor improvement in the DomCrawler + HTML5 explanation

Author: javiereguiluz

components/dom_crawler.rst

@@ -73,8 +73,9 @@ tree.
 .. note::
 
     If you need better support for HTML5 contents or want to get rid of the
-    inconsistencies of PHP's DOM extension, install the `html5-php library`_.
-    The DomCrawler component uses it automatically when available.
+    inconsistencies of PHP's DOM extension, install the `html5-php library`_
+    and the DomCrawler component will use it automatically when the content has
+    an HTML5 doctype.
 
     .. versionadded:: 4.3