Reproduction steps:
1. Open project "RacingConditionMinimalRepro.zip"
2. Build and run

Expected result: "LocTest" Scene gets opened (white text is visible in the middle of the screen)
Actual result: "LocTest" Scene does not load, the screen remains blue

Reproducible with:
2018.4.32f1, 2019.4.21f1: 1.6.0 - 1.17.4-preview
2020.2.7f1: 1.16.1 - 1.17.4-preview
2021.1.0b7, 2021.2.0a6: 1.16.15 - 1.17.4-preview

Reproducible with:
Player on Windows 10
VLNQA00277, Asus ROG Phone, Android: 8.1.0, CPU: Snapdragon 845 SDM845, GPU: Adreno (TM) 630
VLNQA00121, Samsung Galaxy S9, Android: 9, CPU: Exynos 9 Series 9810, GPU: Mali-G72

Not reproducible with:
Editor on Windows 10

Notes:
- Cannot test with versions under 1.6.0 because of: "Assets\Scripts\SceneLoaders\SceneLoader.cs(105,20): error CS1061: 'SceneInstance' does not contain a definition for 'ActivateAsync' and no accessible extension method 'ActivateAsync' accepting a first argument of type 'SceneInstance' could be found (are you missing a using directive or an assembly reference?)"