Ask HN: What's this new annoying popup on GitHub issues/PRs list

Whenever one hovers over an issue or PR, now there is a popup that appears, blocking my view of a number of other items, and when I move away, the popup does not disappear. It may seem like a minor gripe, but this is a huge step back in usability IMHO. I wonder whether the people making these sorts of UI changes have to actually work with the UIs themselves.