Steps to reproduce:
1. Open supplied project

Expected: no crash
Actual: crash

Reproduced in: 2018.3.0a10, 2018.3.0b3, 2019.1.0a2
Not reproduced in: 2018.2.10f1, 2018.3.0a3, 2018.3.0a6, 2018.3.0a8, 2018.3.0a9

Note: if the project does not crash on reproducible versions, delete the Library folder.
The bug only reproduces on .NET 3.5 equivalent Scripting Runtime Version

Stack Trace:
0x00007FFDCE1C333D (mono) [c:\buildslave\mono\build\unity\unity_liveness.c:178] mono_add_process_object
0x00007FFDCE1C357F (mono) [c:\buildslave\mono\build\unity\unity_liveness.c:256] mono_traverse_object_internal
0x00007FFDCE1C387A (mono) [c:\buildslave\mono\build\unity\unity_liveness.c:297] mono_traverse_objects
0x00007FFDCE1C3A78 (mono) [c:\buildslave\mono\build\unity\unity_liveness.c:451] mono_unity_liveness_calculation_from_statics
0x00000001408F0509 (Unity) GarbageCollectSharedAssets
0x000000014099D54C (Unity) UnloadUnusedAssetsOperation::IntegrateMainThread
0x00000001409A0C2B (Unity) PreloadManager::UpdatePreloadingSingleStep
0x00000001409A14F9 (Unity) PreloadManager::WaitForAllAsyncOperationsToComplete
0x0000000141EDBF16 (Unity) AssetInterface::ProcessAssetsImplementation
0x0000000141EE6404 (Unity) AssetInterface::StopAssetEditing
0x0000000141EE0F20 (Unity) AssetInterface::RefreshInternal
0x0000000141EDDE2C (Unity) AssetInterface::Refresh
0x0000000141E95E93 (Unity) AssetDatabase::Refresh
0x000000014131E87C (Unity) Application::InitializeProject
0x000000014148453B (Unity) WinMain
0x000000014246390A (Unity) __scrt_common_main_seh
0x00007FFE37183034 (KERNEL32) BaseThreadInitThunk
0x00007FFE37D01461 (ntdll) RtlUserThreadStart