I've added a mantis report and proposed fix here:

   http://bugs.squeak.org/view.php?id=7251

Cheers,
   - Andreas

Andreas Raab wrote:
> Bert Freudenberg wrote:
>> No, it should be changed to not use Sensor directly.
> 
> Indeed. This is also subtly broken in the presence of multiple hands. 
> What it should do is determine the hand that is dragging it, remember 
> that hand and then use "hand shiftPressed". Unfortunately, this requires 
> the users of TransferMorph to be fixed so that they pass a valid hand in 
> the drag process since TransferMorph itself can't easily figure out 
> which hand is responsible.
> 
> Cheers,
>   - Andreas
> 
>> - Bert -
>>
>> On 22.12.2008, at 00:12, karl ramberg wrote:
>>
>>> So maybe the TransferMorph>>step should have a 'self  delete' if owner
>>> is not a hand morph? Or is there cases where transferMorphs live by
>>> them self ?
>>>
>>> Karl
>>>
>>> On 12/21/08, Bert Freudenberg <bert at freudenbergs.de> wrote:
>>>>
>>>> On 21.12.2008, at 21:06, Julian Fitzell wrote:
>>>>
>>>>> On Sun, Dec 21, 2008 at 8:38 PM, Andreas Raab <andreas.raab at gmx.de>
>>>>> wrote:
>>>>>> Julian Fitzell wrote:
>>>>>>>
>>>>>>> Did anybody ever figure out what the heck is causing this? It's
>>>>>>> driving me nuts!!
>>>>>>
>>>>>> It's users of Sensor>>mouseButtons, Sensor>>shiftPressed etc. The
>>>>>> main
>>>>>> suspect in this regard is TransferMorph which does this:
>>>>>>
>>>>>> TransferMorph>>step
>>>>>>      self shouldCopy: Sensor shiftPressed.
>>>>>>      self updateCopyIcon
>>>>>>
>>>>>> A lingering TransforMorph (which can happen after DnD errors) will
>>>>>> happily
>>>>>> eat all your events.
>>>>>
>>>>> Thank you, thank you, thank you. This fixed it:
>>>>>
>>>>> TransferMorph allInstances do: [:ea | ea delete]
>>>>>
>>>>> (there was a lingering one - it had an omnibrowser method node as a
>>>>> passenger)
>>>>>
>>>>> Not sure why this is happening so much to me right now but at least I
>>>>> have a fix.
>>>>
>>>>
>>>> Oh great! We have encountered this from time to time but never got
>>>> down to the cause. Thanks Andreas!
>>>>
>>>> - Bert -
>>>>
>>>>
>>>>
>>>>
>>>
>>
>>
>>
>>
>>
> 
> 
>