WPF Walks Slowly
WPF is such a great Microsoft software development technology. Its beautiful user interface implement and convenient object properties attached feature, was almost the final technology which was going to replace Windows Form technology;
However, the short point of WPF is too tight with Windows, it needs Windows to support too much, so even it is good, there was no a team or company to let WPF to work cross-platform, which is like Mono project, which convert Windows Form tech works on Linux.
So, along with the time changed to Cross-Platforms, the WPF lost its future, lots of people thought WPF has been dead, even Microsoft itself seems stopped major team on WPF project, they only arranged a small team to maintain WPF, and is going forward very slowly, check Microsoft official WPF blog, there is no enough updating about WPF’s status, the last update was posted on Oct 29, 2015, they mentioned "WPF is Community Projects" and supported in .NET 4.6.1, but I personal think WPF needs cross-platform supported, so it could be long live.