When applying a Landscape Layer Blend of textures to the Material Base Color, the preview does not update or shows black instead of how the material is supposed to look. When you disconnect the layer blend and attach a single texture sample, click apply and save then the material updates in both preview and in level. when the texture is directly connected to the base color of the material the log shows:
This is NOT a regression as the issue also happens in 4.27.2
Result: Preview and Landscape shows material as black instead of how it is supposed to look
Result: Preview and Landscape shows material as should be.
Expected result: Preview and Landscape shows updated material with new layer blend of textures applied
Actual result: The preview and landscape (after apply) show up as black and the log has entry:
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-151129 in the post.