Google is testing another search results snippet hover effect. This one will color the background a light gray shadow like color. We've seen variations of this before (see articles below).

Google Search is testing a new section in the search results titled or named "Background." This includes articles from news publishers, with I guess, more background information than you would find ...

Google is now making it easier to turn off personalization within Google Search results by adding links to the footer to turn off personalized results. Google added a link to “try without ...