Google Ads is testing variations of its Click-To WhatsApp Messages feature. This feature is only available in select regions, but it allows you to enable searchers to click on a "send message on WhatsApp" button. Google is testing various styles of that button.
Arpan Banerjee spotted this and Adriaan Dekker posted on it on LinkedIn sharing that Google is testing various color variations and styles for this send message on WhatsApp button in the Google Ads.
Here are those screenshots:
Again, this is limited to select regions, specifically Argentina, Brazil, Chile, China, Colombia, Hong Kong, India, Indonesia, Malaysia, Mexico, Peru, Singapore, and Thailand. You can learn more about this over here based on my coverage of this last July.
Forum discussion at LinkedIn.
Note: This was pre-written and scheduled to be posted today, I am currently offline for Rosh Hashanah.