Normally in the Camera view, the only drawings and lines that can be erased are those on the selected layer. The Apply to Synced Drawing Layers 
option allows for the inclusion of drawings on layers synced to the selected drawing layer.
Layers are synced when drawings need to be separated on different layers, but need to have the same timing.
How to erase synced drawings
- In the Tools toolbar, select the Erase
tool. - In the Timeline view, select a synced drawing layer. When you click on a synced layer, the other layers that it is synced with will display the link icon.
- In the Tool Properties panel, enable the Apply to Synced Drawing Layers option.
- In the Camera view, start to erase.
Notice that only the selected drawing and its corresponding synced drawings have been erased.
