You may be able to hide the internal PopupMenu that’s spawned after right-clicking, but I don’t recommend disabling the context menu to avoid harming accessibility. It’s there for a reason after all
You can use the Remote scene tree functionality after starting the project to view internal nodes spawned by GUI elements as they’re created.
PS: Please do not bump questions by posting answers that don’t effectively answer the question. Instead, use the comment functionality or post a new question.