Thanks for the fast reply:

1) Problem exists with today's email as well.

2) I cannot recall a day when it was not a problem.

3) Email client is Outlook 365, Version 1902 (current build, updated two days ago).

Responding on behalf of Ray Zinn, a video showing the defect:

Bumping this. 

When I zoom for larger text, the embedded advertising image forces the text to flow past the margins, which of course makes the content unreadable.