How to reproduce:
1. Open the “IN-102980“ project
2. Open Window > General > Test Runner
3. In Test Runner select “Player” and click “Run All”
4. Observe the time it took for the tests to finish
5. Open Project Settings > Player > Other Settings
6. In “Scripting define Symbols” change “PROTO_PROMISE_DEBUG_DISABLE” to “PROTO_PROMISE_DEBUG_ENABLE”
7. In Test Runner select “Player” and click “Run All”
8. Observe the time it took for the tests to finish

Expected result: Tests with “PROTO_PROMISE_DEBUG_DISABLE” run faster (or at least equal) compared to tests with “PROTO_PROMISE_DEBUG_ENABLE”
Actual result: Tests with “PROTO_PROMISE_DEBUG_DISABLE” run slower compared to tests with “PROTO_PROMISE_DEBUG_ENABLE”

Reproducible with: 2021.2.0b6, 2022.3.64f1, 6000.0.52f1, 6000.1.10f1, 6000.2.0b8, 6000.3.0a1
Not reproducible with: 2021.1.0a9
Could not test with: 2021.1.a10, 2021.2.0b5 (Compilation errors: “Feature 'target-typed object creation' is not available in C# 8.0. Please use language version 9.0 or greater.”)

Reproducible on: macOS 15.5 (M1 Max), Windows 10 (by user)
Not reproducible on: no other environments tested

Note: This issue reproduces in IL2CPP, Mono builds and Play Mode