In true Walking Dead fashion, the trailer is pretty darkly-lit, making it difficult to make out the details.
We do know that Season 9 will explore the reality of dwindling resources in the zombie apocalypse, so there may not be a lot of electricity in the settlements anymore.
Interestingly, the piece of Carl’s shirt is not clearly visible in what we’ve seen of Season 9 so far, whether the official episode stills, the new art, or the trailer.
Given Angela Kang’s comments about the women of the zombie apocalypse stepping up in Season 9, it’s probably safe to say that Michonne is doing an excellent job of coping, even if she’s constantly aware of what she lost with Carl’s death.