GLFW just saw release 3.3, the first release for this graphics framework in over 2 years. GLFW is a companion framework to graphics libraries like OpenGL and Vulkan, providing the missing features like window management and input handling in a cross platform and open source manner.
Details of the 3.3 release:
It adds gamepad input via SDL_GameControllerDB, support for Vulkan on macOS via MoltenVK, better handling of high-DPI and scaling, changing attributes of existing windows, raw mouse motion input, explicit support for joystick hats/dpads, user attention requests, transparent windows and framebuffers (where possible), query for monitor work area, more run-time configuration, various other features as well as fixes for a large number of bugs.
You can download GLFW here. GLFW is an open source libpng licensed project that is hosted on GitHub available here. GLFW isn’t the only framework or library providing this kind of functionality. If GLFW isn’t right for you, check out the alternatives available here.