If you search for “Microsoft edge open source” there will come out a lot of blog posts from five years ago praising a Microsoft Press release that announces that edge is open source .
But then, there’s no actual repository, the GitHub is empty, there’s only the MIT license and that’s it
So, they publish the source somewhere or it’s just marketing?
The question about “Where’s the code?” has been answered by another commenter, but a quick observation about “praise” for Microsoft’s decision regarding Edge:
I’m not sure it was praise as much as relief. As someone who lived through the dumpster-fire years of Internet Explorer (IE) dominance, I was relieved that Microsoft wasn’t still going their own way. They would use something more or less standard. I don’t think I was alone in that relief. That may have sounded like praise.
Of course, there’s a completely different question about whether Chrome/Chromium is becoming the new IE, at least in the sense that standards matter less than “the way Chrome does it.” But (hopefully) that’s still an open question.