TB 78.2.0-pre build1, Windows 10, Owl for Exchange 0.7.6

There is one email account set up in the profile connecting to an Exchange Online server via the Owl extension. This basically works, there's no problem with sending and receiving messages.
However, when dragging a message from Inbox and dropping it onto another folder (Read) in the folder pane, this error message appears in the status bar of the main window:
Cannot convert JavaScript object into an array arg 1
[nsIMsgFolderNotificationService.notifyMsgsMoveCopyCompleted]

The good news is, the message actually gets moved from Inbox to Read, but it remains visible in the thread pane while Inbox is still selected.

Current workaround:

1. wait about 2 min, then the error disappears from the status bar, and the message disappears from the thread pane view of Inbox, or
2. select the Read folder in the folder pane confirms the message has indeed been moved to Read. Upon selecting Inbox again, the message is gone from the thread pane view.

There shouldn't be an error in the first place and the message should disappear from the thread pane view right away after moving.

Whether this is a problem of the Owl add-on or Thunderbird itself I don't know. There was no such problem with TB68.
The profile has been upgraded from TB68.

Well, moving messages works in TB, right? So this would be an issue in the add-on.

Please reopen if you can reproduce with add-ons disabled (Help | Restart with add-ons disabled).

How am I supposed to reproduce this with with add-ons disabled, when the Owl add-on is needed to access the account in the first place?

If it can only be reproduced with the add-on installed, then the problem is in the add-on code and needs to be fixed by the add-on author.