Email content not displaying in long threads

Some emails that have a long thread are not showing any content in them.

I received an email today like this, where there was zero content in the email. Not just appended, but a completely blank email.

I know there actually is content in the email because the email views fine using a different email client.

This has happened twice with two separate email threads from two separate people.

When viewing the message, are there three dots in the message body? If there are, what happens if you click on the dots?

Or are the messages maybe being sent from an Apple email application?

There’s nothing at all in the email. They’re not being sent via an Apple email application.

If you right-click on the message body (or where it is supposed to be) and choose View Mail Source, do you see any of the message body in the popup?

No, none of the body appears in the mail source. It’s like the message just doesn’t exist apart from the header. The email has definitely downloaded from the server, but just does not display.

This only happens with long email threads. My other emails are fine.