additional widget styles for kde5

[odin_ago]

After I upgraded to kde5, the list of possible widget styles in kde settings became quite limited. I've tried to investigate more and I learned that there is a package called qtstyleplugins at qt github. But I could not find this package in gentoo, despite it is avaliable in other popular linux distributions, for example, debian, fedora, ubuntu, and also in freebsd. So I am wondering if it is going to be supported by gentoo, and why it is not supported now? Is it known to be buggy or unstable?