-Shader live link build only one shader variant.
-Two shader variant works in the editor.

Steps to repro:
1. Open the attached project > Sample Scene.
2. File > Build Settings > Player Settings > Other Settings.
3. Optimization > Enable "Keep Loaded Shaders Alive".
4. File > Build Settings > Select PC, Mac & Linux Standalone.
5. Enable Development Build > Build & Run.

Actual Result:
Only one cube changes its colour.

Expected Result:
Both cubes change colour over time.

Reproducible in:
2020.2.0a14

Tested on:
-Windows Standalone player.
-WebGL player.
-Universal Windows Platform player.
-Android Player.
-iOS player.

Tested on Android Device:
-Samsung Galaxy Note 9, OS: Android 10, GPU: Mali-G72.
-OnePlus 3, OS: Android 9, GPU: Adreno 530.

Tested on iOS Device:
-iPhone 7, OS: 13.1.2.