performance Indestructible windows turn into Lag Machines

[Ohtrin]

Hello,
I am sorry if it is a known issue but after a (lazy) quick research on the topic I didn't find anyone complaining about it.

I was trying to raid the Mall for the first time, inspired by the Holidays spirit and unfortunately got an unusual extreme frame rate drop. (Pretty normal and acceptable to get lower FPS when playing with insane pop...)

I must confess that was doing what is called a "burn" to clear out the area which involves doing loud noises (Shotguns shots, horns, sirens etc) and set ablaze the massive crowd of zombies that show up. So I didn't mind the frames dropping even further due to such situation. Except as the flames cleansed the zombies from the parking lot. They kept constantly appearing in very small groups and the frames were staying steadily low (all the way to 5 fps as I approach the mall itself). I ran out of time and honestly got feed up with the situation, so quit for a moment. When I loaded the save a mini horde appeared in front of the Mall (almost reaching midway to my character on the other end of the screen). On further investigation I creeped near the door they were slowly pouring throw to find a whole untouched and massive blob of congested zombies stuck behind a thin layer of other zombies trying to break what seems to be indestructible windows.

I understand that the indestructible windows being targetable may serve for a thematic jump scare (if it wasn't for the whole situation and annoyed mood I was, I would have love it). But I think the current situation where zeds clog up there and cannot figure/make a way out isn't just "unfair" or "annoying" but it is actually problematic for performance reasons.

For anyone that is reading this by the end of December, Happy Holidays! =)

[PeacefulTreasure]

Oh, hey, I've actually done a burn at the mall before. Those windows seem to be indestructible, yea, and it led to a massive FPS drop  due to the sheer number of undead that couldn't make it out. I dont' know of anything to be done for it, unfortunately. 

Happy holidays to you as well! I'm sorry I couldn't be of help.