Masking Problem (bug?) - solution included - ZBrushCentral
Hiding & Masking — Blender Manual
Invisible mask areas are generated in Zbrush when exported from Blender to Zbrush if a mesh had mask areas before · Issue #105 · JoseConseco/GoB · GitHub
How to Work With Masks in Zbrush? | Lesson 2 | Chapter 6 | Zbrush 2021 Essentials Training - YouTube