Bing is testing bold text in URLs shown in its search results. The entire URL isn’t bold. The domain name appears in regular weight, while the breadcrumb or category portion of the URL is shown in bold. I spotted this yesterday, and it was new to me.
Here is a screenshot of this.

A change like this can catch a user’s attention, but it’s not clear how it would help the website itself. Bing has tested many SERP changes recently, so this may be one more part of that series.
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