Something very odd happened to the Plugin panel in 5646. After three years with a somewhat whimsical relation to the art of user interface design, the Plugin panel suddenly became ...
clear, clean, informative, and pleasant to use. Nothing fancy or disturbing, just solid functionality solidly expressed.
This is both wonderful and disturbing, like finding out that an old enemy died in his sleep.
The Project Structure (previously Project Roots, previously Modules) panel is also much improved, although it's still got a few issues (right-click menus in the tree in particular).
Since these panels were always neck-and-neck for the coveted "Worst Usability in IDEA" title, it's very good to see them getting positive attention. Good work.