Installing the patched xul.dll file bricks Firefox

[xxHAKRxx]

So I downloaded the patched xul.dll file recommended for this theme, but when I replaced the existing file with the patched one and started Firefox, I was met with these errors:


Since I replaced the .dll file, I had basically bricked my browser and had to uninstall and reinstall Firefox to fix it. I later found out that the theme works fine without the patched file, but it won't affect the window buttons and some text is either white or completely invisible.
One thing I have noticed though is that the original xul.dll file is 135k KB, while the patched one was 128k KB. I dunno if that has to do with the patch bricking my browser, but it's just a guess.

[SomeHuman69]

Probably not using the right version
firefox 115.12 ESR link
patch version to alongside it

[xxHAKRxx]

That was the version I used.
I checked my Firefox version too and it is up to date (I'm on build 131.0). I noticed that the patch hasn't been updated since June, so maybe the patch is out of date?

[SomeHuman69]

I checked my Firefox version too and it is up to date (I'm on build 131.0)

the problem is that you're up to date lul
theme is for firefox 115 ESR
make sure auto updating is disabled if thats messing it up

[xxHAKRxx]

Okay so I downloaded the 115 version and now I'm getting this error when I replace the xul file

[SomeHuman69]

sorry for taking so long

are you using both links i provided d^;
error means you're mismatching versions