I've found it!
It's been in use multiple times each day without realising that it was a decoration. It's one of those things you use, without particularly looking at it. It's a tea bag dish for collecting dead tea bags. There on top of the dish was a snow scene, together with a car carrying a Christmas Tree. There's no kidding yourself it's just a winter scene, it's a Christmas decoration and has now been put away.
Undoubtedly, sometime around June, we will discover a bauble or something else Christmassy which has escaped detection, but at least the first one has been discovered.
Do you ever find stuff way after its put-away date?