View indices of an object modified with Geometry Nodes
Add to Blender addons the usual way
A new operator called GN Index Viewer will be located in the View menu
Select an object and run the operator
It runs in EDIT mode, so you can select any face, edge or vertex in the usual way you would in edit mode
Any changes to the Geometry Nodes will be reflected in the view live
Right Click or hit ESC to end the viewer
Adjusting sliders do not update as you slide, only once letting go of the slider it will update