A diagram in the manual of "soelim(1)" shows that the pipeline is
soelim <file> | preprocessors ... but an actual pipeline with "preconv" (groff -mandoc -s -K utf8 -V input) is preconv -eutf8 input | soelim | troff -mandoc -Tps | grops Using the soelim(1) order the pipeline becomes soelim input | preconv -eutf8 | troff -mandoc -Tps | grops Which is the correct order? See also bug #59442 (10th November 2020) in /https://savannah.gnu.org/bugs/?group=groff and use the 'Search' window to find the bug in the Area 'Bugs' If the pipeline is constructed manually, how would it look like? Why?