Reproduction steps:
1. Open the attached “IN-96013_StrippingRepro” project
2. Click Edit > Project Settings… > Player
3. Under Other Settings, make sure the “Scripting Backend” is set to Mono
4. Make sure that the “Managed Stripping Level” is set to anything other than “Disabled”
5. Click File > Build Profiles > Build
6. In the built Player directory, go to Data > Managed
7. Find “NZSpellCasting.Spells” DLL files

Expected results: “NZSpellCasting.Spells” DLL files exist in the “Managed” directory
Actual results: “NZSpellCasting.Spells” DLL files do not exist in the “Managed” directory

Reproduced with: 2022.3.59f1, 6000.0.40f1, 6000.1.0b8, 6000.2.0a5

Reproduced on: Ubuntu 24.04, Windows 11 Pro
Not reproduced on: no other environment tested on

Notes:

* Reproduces with Mono
* Does not reproduce when the NZSpellCasting package is in the “Assets” directory with any “Managed Stripping Level”