See Rebirth-of-the-Night/Rebirth-Of-The-Night#789

This is fixed in the development branch and will be available in the next feature release 1.12.2-1.6.0.

This fix will not be released immediately as a patch in the main branch because it is an experimental fix that has been tested against the vanilla hopper and Pyrotech's stone hopper, but may introduce unexpected side-effects when used with other mods.