Update release notes

git-svn-id: http://root.cern.ch/svn/root/trunk@31518 27541ba8-7e3a-0410-8455-c3a389f83636

gui/doc/v526/index.html

@@ -14,6 +14,7 @@
 <h4>TBrowser</h4>
 <ul>
 <li>Automatically switch to the tab containing the current canvas (if any) when e.g. drawing a histogram by double-clicking on its list tree item in a root file.
+<li>Automatically switch to (and update) the list of files in the file browser (left panel) when opening a ROOT file from the "Open File" menu
 </ul>
 
 <h4>TGListView</h4>