Trailer: https://www.youtube.com/watch?v=4asbSRyy6qs&ab_channel=Tiedie
This package includes everything you need to start working directly with RGBA masks in the viewport of Substance Painter. This is a common practice used for making masks that will later be needed for shaders, and since it's directly in a 3D viewport there is no guesswork needed like when using other software such as photoshop.
Included is a Substance Painter template files, smart material to work in, export templates for RGB and RGBA options, and an instructional video on how to set up/use everything.