I see a "quota exceeded" error in your logs, and that can result in these grey boxes.
What specifically triggers this error depends on the browser you are using. Some browsers can trigger the error if your device/computer's total storage is approaching capacity. If so, you might want to free up some device storage.
Otherwise, this may relate to the amount of browser local storage the specific site (new.express.adobe.com in this case) is consuming. There are many help articles online that explain, for commonly used browsers, how to clear such storage.