Google AMP has barely launched and Google is already tweaking how those articles are appearing in the Google search results. When Google was in testing and when it launched, all AMP articles had a green lightning bolt icon on them.  But Google has now changed the color to a much less noticeable gray.

Here is how it looks with the new gray icon.

Here is how the icon was originally appearing in the news carousel of the search results when it launched:

It is not clear why Google made this change, although perhaps the bright green detracted from the rest of the AMP results, since it was very eye catching, particularly when it was something new that people weren’t used to seeing.

I also wouldn’t be surprised to see Google do further testing of the AMP icon, similarly to how we see Google testing a wide variety of colored stars too.