I didnt knew before as well but some people here called it “leather jerkin”, many results came up when the phrase is searched. It also should be available for other not so cold maps as well
The Leather Jerkin dates back to the first world war and was essentially a cold-weather “working” item. Most WW2-era jerkins are made from brown leather, with 4 large plastic buttons on the front, and lined throughout in khaki serge. Many jerkins appear of “patchwork” construction, likely due to wartime economies requiring the use of the smallest scraps of leather. The common brown leather colour may vary from a very light orange-tan right through to a dark brown. Jerkins came in 3 main sizes, marked “1 to 3” (smallest to largest). British WD jerkins can still be found today brand-new, but they are getting scarcer and the price seems to be rising. Loads of them were released from storage in the early 1990’s. A “used” example is probably a better bet, especially if you intend to wear it.
In all the images, this thing stands out much more against the soldier’s uniform than in the game. In the game, it blends in too much. Sometimes you have to look really hard to notice it’s there. Perhaps the developers really should make it contrast better. Or make the model more three-dimensional and make the borders stand out more.
I am no expert, just an enthusiast about Commonwealth gear.
The only thing I can state is that I know of no such occurrences.
This does make sense though, greatcoats existed and were in use, and would likely be preferable over stacking both of the previous items together. But, I still leave open the possibility that it could have happened.