That’s not a blooming holiday ??
candlesticks ? pictures, empty frames, books, teapots, decorative plates, vases. That's all I can think of for now.
Same problem with one of my pellet stoves when its not in use!! Currently it holds a decorative metal tricycle with one small teddy bear on it and another smaller one near the bigger front wheel. Sometimes its different ceramic angels or carousel horses or a silk flower arrangement. Use decorative items that do not have a holiday theme.
With narrow items you like. Tall topiaries on each end. Mantel clock on center it decorative painted box, a few family photos, figurines, anything you want that works,with your decor.
Mine changes seasonally with at least a nod to any holiday. Here are some designer tips and tricks.