increased randomness of file name used in is_really_writable()
diff --git a/user_guide/changelog.html b/user_guide/changelog.html
index 6ec6cd3..a6eaef1 100644
--- a/user_guide/changelog.html
+++ b/user_guide/changelog.html
@@ -76,6 +76,7 @@
 
 <h3>Bug fixes for 1.7.3</h3>
 <ul>
+	<li>Increased randomness with<kbd>is_really_writable()</kbd> to avoid file collisions when hundreds or thousands of requests occur at once.</li>
 	<li>Fixed or clarified assorted user guide typos or examples.</li>
 </ul>