I noticed what appears to be a new ad marker today alongside Google Ads Search Network results. Also, the display URL has been moved to the top of the ad next to the ad marker above the ad title. The ad marker is a played down version of the previous label which was Green and contained in a border.
New Ad Label Noticed January 2020.
Previous Google Ads Label
I happened to take screenshots just the other day (1-13-2020) and the ad marker looked like this:
Google has changed the ad markers numerous times over the years and I am confident we will continue to see the ad markers continue to change.