When I create a mask, a configuration automatically pops up. I have been resetting the mask so I can do what I want, but where is this preset coming from. I have no presets set.

Lightroom classic - 

1. I create a virtual copy, so am working on copy 1
2. I press the mask icon and I can select whatever mask I want, 
3. Upon selecting mask, a configuration appears as if it is wired in.  
4. I have no presets configured.  
5. I can reset the mask and then do whatever I want.