In some Chapters of Celeste, you'll find three yellow bulbs, which (after you make proper moves) follow you and combine to make a strawberry. (Sorry, but I can't find a proper picture - on top of head I saw it in Chapter 2, Chapter 4). The only thing that makes them follow is when Madeline's hair is Blue (i.e dashed), but I don't know what's the exact mechanic that makes them move. Any ideas ?
These strawberry fragments don't actually respond to hair colour. You can just pick them up like a strawberry by moving through them. However, you'll lose them as soon as you touch the ground. That means you need to remain in the air until you've collected all of the fragments (either by clinging to or jumping from walls or by refreshing your dash without landing).