sjvn, 
It's baaack! Microsoft and IBM #opensource MS-DOS 4.0 https://www.zdnet.com/article/its-baaack-microsoft-and-ibm-open-source-ms-dos-4-0/ by @sjvn
How did the operating system so bad it likely steered users to #Linux 35 years ago come to be open-sourced now? Here's how.
