Microsoft Bing seems to be promoting TikTok video results within the Bing search results. If you do a search for some videos, Bing might add a box on the left side by the video search results box that says "Short videos of X" with a "from TikTok" button.
This was spotted by Frank Sandtmann who posted this GIF on Mastodon:
When you click on the box it takes you into Bing Search video results for a query [Videos from TikTok].
I can replicate this for many video queries in Bing search, so I don't think this is a test.
I have no idea if there is some sort of paid placement for this or just a feature the Bing search engineers found to be cool.
Forum discussion at Mastodon.
Update: Microsoft posted about it several weeks later:
The rising popularity of short video on TikTok and elsewhere is no surprise—it's a quick and entertaining way to learn something new. We've incorporated short video throughout Microsoft Bing #Search results to help users find what they're looking for in their preferred format. pic.twitter.com/YmP0WSYkgN
— Jordi Ribas (@JordiRib1) January 4, 2023
Update: Another variation spotted by Frank Sandtmann on Mastodon.