What is really missing?

I wonder how I managed to live without this tool for the last few years.
I've been running my feet off from factory to factory just to find the culprit.

• fork of the What is Missing mod from Zomis
• this is not a official successor of the existing mods, but a solution for my needs
• adapted for Factorio 2.0
• basically works with Space Age, but is not yet adapted for all features.

Credits

Thanks goes to
zomis