I forgot to write that only elements form the current frame can be selected
and deleted.
When a library item is opened, the first frame is the current frame.
Use timeline.setSelectedLayers() and timeline.setSelectedFrames()
I forgot to write that only elements form the current frame can be selected
and deleted.
When a library item is opened, the first frame is the current frame.
Use timeline.setSelectedLayers() and timeline.setSelectedFrames()