In Nova Scotia, Canada ours does have an identifying detail. It has the number of the relevant inspection. It’s suppose to be applied by the garage. You as the car owner are not suppose to be able to remove and reattach it.

The other guy is right. If the colour matches and the month is good they won’t catch it unless they are being super careful. It’s not 100% but like 95%.

Someone needs to look closer than they actually would to check that level of detail. If you have the right color for this year you are good unless they really want to get you for something else.