When viewing your email published to SFMC in Chrome, some images can be pixilated or replaced by a blank area or a predictable placeholder. You can fix this issue by setting the image rendering in Google Chrome.
For this:
1. Go to your SFMC account.
2. In the browser address bar, click the icon to the left of the web address.
3. Select Site settings
.
The Settings
page opens in a new tab.
4. In the Permissions
list, find Insecure content
and select Allow
for it.
Your changes are saved automatically.
5. Reload the SFMC page to apply your settings.
Read more