Unable to send screenshots to Freeform on iPhone 13 after iOS 18.3 upgrade

Prior to upgrade to iOS 18.3 on my iPhone 13, I was able to send a screenshot to Freeform (while running in iOS 18.2).

steps to reproduce:

1. Take a screenshot using 2 button technique
2. Then send the screenshot to the "Freeform" app.
3. Choose an existing board, or create a new board (both fail)
4. Click Save

When this worked, the screenshot would be visible in the chosen Freeform board. With iOS 18.3, this is not working.

Sending the screenshot to other apps, like Messages is still working OK.

[Re-Titled by Moderator]