Finding missing component

Hi, I am opening up my grasshopper definition that I did few months ago and I figured out a component is missing. Grasshopper just does not show that component. Is there anyway I could figure out what is missing? So I can find that plugin and install. Please advise

If it was a plugin, there should have popped up an error message when opening the gh file. Was that the case?

Maybe it has come up at some stage and I ignored it.

Hi - if you haven’t saved the definition in its current state, if you close it and reopen it, that error message should appear again.