Email chain incorrectly marked read

Mail
1

I believe we have found a bug.

Environment:
Microsoft 365 email account and Exchange Web Services, server: https://outlook.office365.com/EWS/Exchange.asmx
Settings > Mail > Read > Conversations: Disable conversations is set.
Folder A
Folder B
Email Chain 1.a
Email Chain 1.b
Email Chain 1.c

Scenario:

  1. Email Chain 1.a, Email Chain 1.b, and Email Chain 1.c are all unread and in Folder A.
  2. Email Chain 1.b is moved to Folder B
  3. Folder B is right clicked and “Mark All Messages As Read” is selected
  4. Email Chain 1.a, Email Chain 1.b, and Email Chain 1.c are all marked as read even though only Email Chain 1.b should have been marked as read.

If Email Chain 1.b is right clicked and marked as read while in Folder B then Email Chain 1.a and Email Chain 1.c remain unread as expected.

Would it be possible/likely that this behavior can be fixed?