I've updated from version 8.4.4 (installed from the official Ubuntu Package repository) to the 9.0 (using apt-get) on a Ubuntu 16.04 system. Xwiki is running on Tomcat 8 and uses MySQL.
After the installation wizard, I've been redirected to the Main page, where I could still see the navigation tree on the navigation Pane, with only the first level pages. All the other pages (depth > 1 where 1 = Main page level) is lost.
When I try to reach the page from the direct link, I still see the page and I can also edit it.
Seems like I'm missing the tree structure on the Navigation pane.
Someone with the same problem?
Note: Entering the page with direct link, I can see the correct breadcrumb: Home > Root Page > Second Page