This bird seems different. Lighter overall by comparison to the others. Lighter underparts with less or lighter streaking. Rounded posture. Pushed-in look to face (feathers around bill). Behavior: this bird frequently appears alone, often the first one in the morning light, or the one that stays when the flock leaves. There has been at least one frosty bird in the redpolls that have been here for several weeks.
I think the same bird that appeared alone on 3/4/21. Rounded, frosty overall. Basking in the morning sun. Stayed behind to eat alone once a dozen or so Common Redpolls came and left