It means that the component is part of and is linked to a global. If you right click the component it can be unlinked from its global. When a component is linked to its global then changes to that component will also affect other instances of the global. When the component is unlinked from its global then changes will only affect that specific component.
Hope that makes sense!
Thanks @maxken. It is a bit confusing. So I guess in this case the Footer is the Global, and the Flex and Text are linked to the Footer Global. And when I look at my other Globals, I see linked components inside them too. OK, this helps me understand.
Yes, that’s the way I understand it’s designed to behave. Unlinking a component within a global isolates it from changes made to other instances of that global and other instances of that global are not affected by changes to the unlinked component.