Microsoft is testing placing search refinement tabs or buttons above the shopping ads within the Bing Search results. And when you click on those refinements, you are taken into Bing Shopping Search.
Normally those refinements are not shown above the search ads carousel, so that is new.
Here are screenshots from Sachin Patel on X:
Forum discussion at X.
Note: This was pre-written and scheduled to be posted today, I am currently offline for Simchas Torah.