https://issuetracker.unity3d.com/issues/terrain-does-not-support-setting-the-renderinglayermask-filters-used-by-srp-slash-hdrp
Unity Issue Tracker - Terrain does not support setting the renderingLayerMask filters used by SRP /...
Merged PR at e71028a96af9 to trunk in 5876ceb54d0b.