In the Environment options, quite possible for all options however I have only had extra ground textures thus far, the scrolling interface for Ground textures is what I believe would be called bugged. This appeared after adding more textures via
Demian's add-on, though I'm certain this would happen with any new additions.
Basically, the interface can see all textures, but can only select what is within the scroll-box area. Everything else is unselectable, and will also scroll oddly. When you click on the others outside said box, the tab will go behind the Environment interface, but only when you click on the unselectable textures that are in front of the Environment tab.
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