Sketchup for Web doesn’t have an option for removing unused components. My work-around was to make a component of my drawing (component # umpteen) and save (Drawing1.skp). I then opened a new file and imported Drawing1.skp and exploded it. Only those components within the exploded drawing appeared in the components list.
Yes it does. When you are looking at the In Model components, there’s a Purge button at the bottom of the Components panel.
I stand corrected. Thank you.