Bing seems to be testing added “learn more” cards under the knowledge panel within the search results. The learn more cards are in a carousel format that you can slide through to learn more about the topic from third-party websites.
Here is a screenshot of this from Shameem Adhikarath on X (click to enlarge):
Shameem shared more screenshots and before and after shots in these posts:
here is the previous version pic.twitter.com/1LFPgyEWTI
— Shameem Adhikarath (@shemiadhikarath) September 21, 2023
Again, I cannot replicate this.
Forum discussion at X.