When using an empty map stack of 1, the scoreboard will not recognize it, but a stack of two or more will register

Steps to reproduce:
1) Enter the commands "/scoreboard objectives add maps stat.useItem.minecraft.map" and "/scoreboard objectives setdisplay sidebar maps" to make a 'maps' scoreboard objective and put it on display
2) Open the creative menu and get 2 empty maps, then stack them together into one hotbar slot.
3) Use one of the maps, and watch the scoreboard value, whether it changes or not
4) Use the remaining map, and watch the scoreboard value, whether it changes or not

If you followed the steps correctly, your 'maps' value should've gone up the first try, but not the second.

You can use any quantity of maps stacked and the scoreboard will 'see' it, but if it is of 1 quantity, it won't work

The attached screenshots were taken in order (left to right), and demonstrate the problem