How to reproduce:
1. Open Unity
2. Load tester-submitted project
3. Open 'copyTextureTest.unity' scene
4. Play the scene
5. Go to 'Main Camera' object
6. Investigate each Texture in 'CopyTextureTest' script

Expected result: All textures contains the same color
Actual result: 'Dst Tex 64' and 'Dst Tex 32_A' have no data that resembles 'Src Tex' Texture.

Notes:
It seems that the method only writes first source texture element to the destination texture.

Reproducible with - 5.6.4p3, 2017.1.2p3, 2017.2.0p4, 2017.3.0b11, 2018.1.0a7