Open the Scheduled Transaction Window. Select a transaction and click on the Edit button. The Edit dialog appears as expected and the highlight in the SX list fades as expected because that window no longer has the current focus. Now click on the OK button in the edit window. That window closes, but when the focus returns to the SX list the highlight disappears instead of recovering the current focus. Thus it is no longer possible to see which transaction was last selected for editing. I am using release 2.6.6 in Windows 7 to demonstrate this bug.
I have added a fix for this and will be in the next version 4.6