Replit - what do different colors mean?

My replit repl page looks like this after doing some of the lessons:
image

My question is:
What is the difference between image and image ?

Not sure it really means anything. It might have to do with the node version or language that was detected at the time of creation. Or just when the icon got switched to a new one.

If I start that headerparser boilerplate now I get the same icon as the two other Replits. So it might just be a new icon used now.