WhatsApp message preview disappears from phone lockscreen once the image preview appears on the watch

Hi all. For the last 1-2 weeks I noticed that sometimes when I receive WhatsApp messages, they are not displayed on the phone lockscreen anymore. Today I could observe what's happening:

When I receive a message with an image, it is first displayed on the phone lockscreen. Then, quickly afterwards, I receive the notification on the watch, without image preview at first. Some seconds later, the image preview gets visible on the watch, and as soon as this happens, the notification completely disappears from the phone lockscreen. Not only the image disappears from the phone lockscreen, but the whole notification. Only when I unlock the phone, I can see the notification again. 

Phone is a Pixel 6a on the latest Android version. Anybody else experiences this?