Steps to reproduce:

1. Log in to back office.
2. Go to Admin / Content structure.
3. Start creating a new content e.g. Folder (Send content to review for e.g. administrator user).
4. As administrator user open notifications.
5. Click on notification.
6. Verify styles for read notifications.

Actual result:

See attached screenshot.

Incorrect styles for read messages.

Expected result:

Properly styled graphics for read messages.