We have several hundreds groups in AD.
When I wan to add a permission to fisheye repository I have to scroll down a huge list (or use Cmd+F).
Then selecting a checkbox is a bit tricky because you may by the mistake click a row below or up of the group of your choice.

Adding a spimple CSS :hover rule which darkens hovered row should be great solution.

It would be even better if we there was a ajax group selector like in Stash.