How to reproduce:
1. Open attached project "ConstructionModeling_stripped13.zip"
2. Observe the Editor (if it does not crash try opening it a second time)

Expected result: project does not crash and opens up
Actual result: project crashes

Reproducible with: 2020.1.0b2, 2020.1.0b9
Not reproducible with: 2018.4.22f1, 2019.3.13f1, 2019.1.0b1, 2020.2.0a1, 2020.2.0a11

Notes:
1. Shader Variant with Standard/ForwardAdd DIRECTIONAL shader assigned in Project Settings -> Graphics -> Shader Preloading
2. SourceAssetDB file present in Library

Workaround:
1. Do not include ForwardAdd DIRECTIONAL Standard shader in the Shader Variants
2. Delete SrouceAssetDB file (this will let you enter the project until the next project opening)