The Store listing (thanks to @stanzillaz for digging it up) describes Windows Terminal preview as a "very early preview release" with "many usability issues, most notably the lack of support for assistive technology."
The new open-sourced Windows Terminal app will include multiple tabs, Unicode and UTF-8 character support, a GPU accelerated text rendering engine, and custom themes, styles, and configurations, Microsoft officials have said.
Microsoft published the source code or Windows Terminal on GitHub alongside its existing Windows Console Host, aka conhost.exe, the original Windows command-line app. Console Host's main mission following the announcement of Windows Terminal is backwards-compatibility with existing console subsystem apps, officials have said. Windows Terminal will install and run together with Windows Console.