Thanks for including the profile screenshot. Can you share your interpretation of the profile results?
It looks to me like the bulk of the time is spent in jQuery. Can you verify with the network tab that the component is not waiting on some ajax request?
Sorry for the response delay (holidays).
The file "combo_list_shadow.png" is already loaded and the "network" tab is empty (thanks FireBug).
I agree the time is spent in jQuery and I don't understand why this problem only append some times. If the problem is jQuery (itself or in a call), the problem will always append...
If you get rid of the this.rf.component.__updateItems() call from your onlistshow handler, does the problem go away?
This call is used to clear the "input:text" and display the whole list.
We will find an other way.
Thank you for your response.