Microsoft invited free software legend Richard Stallman to speak at its Microsoft Research headquarters this week. Stallman, known for launching the Free Software Movement to develop the GNU operating system, was and still is a staunch Microsoft critic.
Update: One attendee of Stallman's talk, Microsoft software engineer Pedro Paulo provided me with a few of the topics discussed when I asked him on Twitter. He said Stallman gave a "mostly standard talk," covering the importance of free software, GPL v3, GNU vs. Linux. He added that "he had a list of 'small requests': make Github push users to better software license hygiene, make hardware manufacturers to publish their hardware specs, make it easier to workaround Secure Boot."
If you're wondering whether Stallman's distaste for Microsoft has lessened over the years, his personal home page makes it clear that it has not. The front and center of his main page is a list of "Reasons not to use Microsoft." The list is current, and includes "Microsoft recorded users of Xboxes and had human workers listen to the recordings," and "Microsoft tricked users into 'upgrading' to Windows 10.'"
Each time Microsoft makes another open-source-related move these days, there are still always folks on Twitter or in comments on blog posts who caution that Microsoft hasn't really changed and never will be a true friend of open source. This change in Microsoft didn't happen overnight, but the momentum is growing.