At the ongoing CppCon 2019 conference these days, Microsoft
The development of this library is planned to be further developed as an open project developed on GitHub, accepting pull requests from third-party developers with fixes and the implementation of new features (participation in the development requires signing a CLA agreement on the transfer of property rights to the transferred code). It is noted that moving the STL development to GitHub will help Microsoft customers track development progress, experiment with the latest changes themselves, and help review incoming feature requests.
Opening up the code will also allow the community to use off-the-shelf implementations of features from the new standards in other projects. For example, the code license is chosen to allow code to be exchanged with the library
Of the key goals of the project, full compliance with the requirements of the specifications, ensuring high performance, ease of use (debugging, diagnostics, error detection tools) and compatibility at the source code and ABI level with previous releases of Visual Studio 2015/2017 are called. Among the areas that Microsoft is not interested in developing are porting to other platforms and adding non-standard extensions.
Source: opennet.ru