Attempting to delete a layer on 2D Tileset causes NRE

[trundlr]

Object reference not set to an instance of an object.
System.NullReferenceException: Object reference not set to an instance of an object.
   at SpriteTools.TilesetTool.TilesetLayerListControl.DeleteLayer(Layer layer) in C:\Users\aiden\Development\S&box Projects\battle\Libraries\facepunch.spritetools\Editor\Tileset\TilesetTools\LayerControl\TilesetLayerListControl.cs:line 149
   at SpriteTools.TilesetTool.TilesetLayerControl.Delete() in C:\Users\aiden\Development\S&box Projects\battle\Libraries\facepunch.spritetools\Editor\Tileset\TilesetTools\LayerControl\TilesetLayerControl.cs:line 175
   at Editor.Option.OnTriggered() in C:\build\_work\sbox\sbox\engine\Sandbox.Tools\Qt\Option.cs:line 176
   at Managed.SourceTools.Exports.Editor_Option_InternalTriggered(UInt32 self) in C:\build\_work\sbox\sbox\engine\Sandbox.Tools\Interop.Tools.cs:line 21012