Reproduction steps:

1. Create a New Project
2. Switch to .NET 4.x
3. Build a Standalone Player
4. Attach Visual Studio with Symbol Server enabled
5. In "Modules" search for "mono-2.0-bdwgc.dll"
6. Right Click -> "Symbol Load Information"
7. See that "mono-2.0-bdwgc.pdb: Cannot find or open the PDB file."

Expected Result: "mono-2.0-bdwgc" is loaded from the symbol server
Actual Result: "mono-2.0-bdwgc" is not loaded from the symbol server

Reproduced with: 2019.2.0a10, 2019.1.0b10, 2018.3.11f1, 2017.4.24f1