[Feature Request] Optionally suppress display of node data when it is not available.

[rvijayc]

I recently started using this tool and I find it very useful.

In the example below, some node data json files have entries for only a subset of nodes, but I don't see an option to prevent the display of node information for nodes that don't have any entries - they still show up as "-" everywhere which is cluttering the display.

If there is a way to suppress these, please let me know. If not, please consider this a new feature request.

Appreciate your help!