Using Xojo 2019 1.1 and earlier versions, sometimes a selected Method or Property cannot be deleted. If you select the method or property so it is highlighted in blue then either press Delete button or choose the Cut or Delete command from Edit menu nothing happens.
Once a specific method or property gets into this state, it can be renamed, but never deleted (even after closing project, rebooting, etc.) Over time our Desktop and iOS projects have accumulated dozens of these methods and properties that can NEVER be deleted.