Landscape Material renders with missing components when using a 'Landscape Visibility Mask' and deploying to a mobile device. I have found this issue now with an Android and iOS device.
I was able to reproduce this issue in main as well as the most recent binary release 4.7.5
1. Create a new Blank Project without Starter Content
2. Create a new Landscape (used 4x4 component size)
3. Create a new Material and add a Vector 3 Constant with a bright color.
4. Set the material's 'Blend Mode' to 'Masked'
5. Add a 'Landscape Visibility Mask' node and connect it to the 'Opacity Mask' input.
6. Under 'Usage' for the material properties, be sure 'Used with Landscape' and 'Used with Static Lighting' are checked.
7. Apply and Save the material.
8. Select your landscape and apply the material to both the regular landscape material, as well as the landscape hole material.
8. Place a 'Lightmass Importance Volume' around your landscape.
9. Build All and Save All.
10. Open the 'Project Settings' and be sure under the 'Maps and Modes' section 'Game Startup Map' is set to the current map.
11. Select the 'Launch On' option and choose the android device mentioned.
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