Get it FREE on Gumroad:
https://gumroad.com/l/midchecker
On Artstation Marketplace:
www.artstation.com/alexliuzinan/store/pVdk/mid-checker
A little debug filter for Substance Painter. Drag and drop it on top of all layers to quickly visualize where the mid value of your height map is, as well as regions above and below the mid value.
Tested with Substance Painter 2019.2.3, might not work on lower versions.