How to reproduce:
1. Open user's attached project ("2019.3 test project.zip") using the EnvIronman VM (more information in Edit)
2. Load "Bug scene" scene
3. Tick "Compress During Start" found on "Compress(Script)" (Hierarchy -> Grid -> Tilemap)
4. Enter the Play mode

Expected result: no GameObjects are destroyed after entering the Play mode when "Compress During Start" is checked
Actual result: part of GameObjects created by RuleTiles are destroyed after entering the Play mode when "Compress During Start" is checked

Reproduced with: 2019.3.0a12, 2019.3.0b9, 2020.1.0a11
Not reproduced with: 2019.2.11f1, 2019.3.0a11
Could not reproduce with: 2017.4.33f1, 2018.4.12f1 (various dependency errors, including ones related to 2D Tilemap)

Notes:
- amount of GameObjects in the scene can be checked by right-clicking on "Compress(Script)" and selecting "Count game objects"