Since some days the graphs in the product main page cannot be loaded, only show-up as broken image link symbols.
Example:
https://build.kde.org/job/KDevelop/job/kdevelop/job/kf5-qt5%20SUSEQt5.9/
Inspecting the respective links it shows the GET requests are returning 500, invoking the links directly in the browser shows an Ooops page with a Java stack trace.
Example:
https://build.kde.org/job/KDevelop/job/kdevelop/job/kf5-qt5%20SUSEQt5.9/test/trend