Eduardo posted latest updates from his work on XOOPS 2.6.0 GUI (or Presentation Layer)
New settings manager for modules. The new design is cleaner and responsive to maximize its functionality.
Dynamic settings. System is capable to load options dynamically to improve the development flow and updates. Avoiding the old form tabs based on jQueryUI. Now bootstrap is fully integrated with tabs and, with this change, I'm prevent to embed HTML code in form PHP files.
Also the users management has been ported to new GUI.
Groups management has been ported to new GUI.
More info about XOOPS 2.6.0 GUI and Eduardo's work: on GitHub