When deleting/flagging as junk the bottom-most mail, no mail is selected in the view any more. This has the disadvantage that after leaving and reentering the current mail folder, the view is scrolled back to the very top.

The behaviour is correct, when deleting/flagging as junk a mail that is NOT on the very bottom. In this case the following message is being selected, yielding the expected behaviour (in keeping the view as it was even after leaving the folder).

The proposed behaviour in the case that the deleted message in fact is the bottom-most message, is to select the message before the deleted message.

All this holds for ONLY ONE message being deleted/flagged as junk.

The wrong behaviour can also be observed when multiple messages are selected. In this case it should be defined which message to select after the deletion/flagging operation. In my opinion it should be the position of the most recently message added to the selection +1 (or -1 if already at the very bottom).