Steps to reproduce:

1) Download attached project 'lobby_spring_prop_trophy.zip' and open in Unity
2) Make sure Graphics API is set to GLES3 in Player Settings
3) Build and Run 'test' scene on a device

Note: Shader will fail to render on Mali GPU devices when using ColorMask 0(some parts of this model will be transparent with artefacts) (check attached image 'actual.png').
Expected result: Shader should not fail to render a model when using ColorMask 0 (check attached image 'expected.png')
Works fine when using GLES2

Reproduced with:
5.3.7p4, 5.4.5p1, 5.5.3p1, 5.6.0p2, 2017.1.0b1

DUT:
Reproduced with:
Samsung SM G925F (Galaxy S6 Edge), OS:6.0.1, CPU:arm64-v8a, GPU:Mali-T760, Build:samsung/zeroltexx/zerolte:6.0.1/MMB29K/G925FXXU5DQA7:user/release-keys
HUAWEI EVA L19, OS:7.0, CPU:arm64-v8a, GPU:Mali-T880, Build:HUAWEI/EVA-L19/HWEVA:6.0/HUAWEIEVA-L19/C432B182:user/release-keys

Not reproduced with:
Verizon SM G930V (Galaxy S7 Verizon), OS:7.0, CPU:arm64-v8a, GPU:Adreno (TM) 530, Build:Verizon/heroqltevzw/heroqltevzw:7.0/NRD90M/G930VVRU4BQA2:user/release-keys

Xiaomi MI MAX, OS:6.0.1, CPU:arm64-v8a, GPU:Adreno (TM) 510, Build:Xiaomi/hydrogen/hydrogen:6.0.1/MMB29M/V7.5.1.0.MBCCNDE:user/release-keys