When trying to add clips to an existing project, Kdenlive locks up or crashes.
This happens regularly, but not always.

Detail:
Open an existing project
Remove item on timeline - see note below
Click dropdown to add clip to project
Dialog opens and application often locks up before anything else can be clicked
Alternatively, application sometimes crashes without opening the dialog at all

Note
This seems to be more prone to happening after removing an item from the
timeline