The groom changes when moving the vertices on the distribution surface 



The groom changes when reloading the scene after moving the vertices on the distribution surface and saving the project.



Hair from Guides roots are remembered, but the guides before them in the stack are not. Because guides are generated using area-based approach (Even distribution, which is the default) they will be generated differently on scene reload. The loaded hair still assumed previous guides since it was remembered, but their number and order changed due to them being regenerated.


Solution 1 

Change root generation in GFM to Vertex, Face, or UV-based.


Solution 2 

Use "Remember Roots" button on guides as well.

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