The new gizmo toggle controls backdrop gizmo visibility for the compositor node editor. The implementation is consistent with the image editor, where the gizmo toggle has a menu with a single entry, instead of having no drop down menu at all. The new toggle will be set inactive when there is no node tree in a follow up PR: https://projects.blender.org/blender/blender/pulls/139526 Pull Request: https://projects.blender.org/blender/blender/pulls/139525