Microsoft is internally testing several new features for Windows 10 and these changes could be shipped with the 19H1 update next year. As highlighted by Microsoft watcher on Twitter, the company is working on Microsoft Flow-powered actions for Action Center, independent dark theme toggle for File Explorer and more. Windows 10’s built-in Task Manager is projected to receive another feature where users will be allowed to choose any of tabs (performance, app history, startup, users, details and service) to be the default one. Microsoft is also testing some new changes potentially related to voice assistants such as Alexa.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-to-get-new-task-manager-action-center-and-file-explorer-features/