Created attachment 104405 [details]
Attachment showing kmail window in the state where the described behaviour can be observed.

This still happens although #368743 is supposed to be fixed:

Whenever one of kMails frequent and lengthy folder synchronisations takes place, the focus is always stolen from the quick search bar after switching to a new folder.

To reproduce (also refer to screenshot):


* The account "Lokal" refers to an IMAP account on a locally running
  IMAP server in my case.

* Click at a folder which requires a while to synchronize. The Sent folder
  might a good idea, mine always takes about 2 minutes to synchronize whenever
  I open it.

* Click any mail in this folder such that the "please wait" message you can see
  in the screenshot appear.

* Now select another folder and click into the quick search bar.

What now happens is that after a delay of about 1 or 2 seconds, the "please wait" message will redraw, at which point the focus will be stolen from the quick search bar.

Any search text currently being entered at this moment will be interpreted as hotkey presses, causing chaos... ;)

As this happens all the time, this is pretty annoying.

If this can't be fixed, the quick search bar at least should be disabled for the period during folder switching while it actually cannot be used.