G92 X118 Y72.5 Z0 E0 B0; set (rough) reference point (also set E and B to make GPX happy). This will be overridden by the M132 below but ensures correct visualisation in some programs.
Also, the x3g file isn't being moved to the final target, its staying in /tmp/, which looks like prusa3d/PrusaSlicer#6952
333,334c333,340
< print "Executing: ${gpx_esc} ${arg_p} -m \"${MACHINE}\" ${in_esc}\n" if($verbose);
< my $gpx_out = qx(${gpx_esc} ${arg_p} -m "${MACHINE}" ${in_esc} 2>&1);
---
> my $out_esc;
> if ($ENV{'SLIC3R_PP_OUTPUT_NAME'}) {
> $out_esc = $ENV{'SLIC3R_PP_OUTPUT_NAME'};
> $out_esc =~ s/\.gcode$/\.x3g/g;
> $out_esc = shellEscape($out_esc);
> }
> print "Executing: ${gpx_esc} ${arg_p} -m \"${MACHINE}\" ${in_esc} ${out_esc}\n" if($verbose);
> my $gpx_out = qx(${gpx_esc} ${arg_p} -m "${MACHINE}" ${in_esc} ${out_esc} 2>&1);
[2021-09-25 20:42:53.379256] [0x00007f3c94ff4640] [error] GCodeProcessor encountered an invalid toolchange, maybe from a custom gcode.
Highest Z coordinate found: 150
Fixing incorrect M104 command for single-extrusion setup
Ensuring correct display in gcode.ws
Running retraction script...
Executing: "/usr/local/bin/retraction-improver.pl" -o "/tmp/LnDay2lQQu" "/tmp/.108708.gcode.pp"
Invoking GPX...
Executing: "/usr/bin/gpx" -p -m "fcp" "/tmp/.108708.gcode.pp" "/home/simon/PinHeaderSnappingJig.x3g"
Highest Z coordinate found: 150
Fixing incorrect M104 command for single-extrusion setup
Ensuring correct display in gcode.ws
Running retraction script...
Executing: "/usr/local/bin/retraction-improver.pl" -o "/tmp/GypogpiayX" "/home/simon/233.gcode"
Invoking GPX...
Executing: "/usr/bin/gpx" -p -m "fcp" "/home/simon/233.gcode"