Previous email disappears after responding to it

After replying to an email in the panel view, the previous message in the same conversation disappears. See the attached screenshot. The only way to view it again is by switching to a different email and then returning to the conversation.

I don’t believe this is an installed theme issue as it applies to all of them.

I hope this gets attention and is resolved. I’ve noticed similar threads about this dating back to 2020 that seem to have gone unnoticed.

Is anyone else seeing this? Thank you!