Tiki Trac instance
This Trac instance was enabled for the only purpose of supplementing SourceForge's ViewVC for browsing the Subversion repository, following an issue discussed at http://viewvc.tigris.org/ds/viewMessage.do?dsForumId=4255&dsMessageId=2628748
Click "Browse Source" to browse the source.
The main advantage of Trac is it enables to "follow copies" in file revision logs. For example, if you look at the history of userslib.php in branch 5.x, ViewVC only shows revisions following the branching of 5.x. Trac does the same thing by default, but you can see the full history by selecting "Follow copies" as Revision Log Mode (and, in some cases, increasing the number of revisions shown per page).
The arrows to expand pointing right at the left of directory names are known to be broken: https://sourceforge.net/apps/trac/sourceforge/ticket/12227
Click on folder names instead.