One thing that is a problem when developing MC is that it still kind of support Windows XP.
MC is not tested on XP but it is built to work on XP. and this is a problem.
A lot of new things have been added to Windows since XP SP3 was released.
Some part of MC can use the new features on new platforms but it is a pain and require a lot of extra work.
But it is not just new OS feature that is a problem, MC is built using the C++ programming language, And C++ have got a lot of new language features in recent years and some of them I cannot use since I have to build MC with Visual Studio 2013.
VS2015 do have XP support but it is broken, And I can't use it and Microsoft will not fix it. And later this year C++17 will be released with even more new C++ features that I want to be able to use. And I need to be able to build MC using a modern C++ compiler. I can't be stuck on VS2013 forever.