/usr/share/librecad/library/elektro/opto/ is in librecad-data 2.1.2-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/librecad/library/elektro/opto-iso/Optocouple-trans.dxf
/usr/share/librecad/library/elektro/opto-iso/Optocouple-triac.dxf
/usr/share/librecad/library/elektro/opto/ve1.dxf
/usr/share/librecad/library/elektro/opto/ve10.dxf
/usr/share/librecad/library/elektro/opto/ve11.dxf
/usr/share/librecad/library/elektro/opto/ve12.dxf
/usr/share/librecad/library/elektro/opto/ve13.dxf
/usr/share/librecad/library/elektro/opto/ve14.dxf
/usr/share/librecad/library/elektro/opto/ve15.dxf
/usr/share/librecad/library/elektro/opto/ve16.dxf
/usr/share/librecad/library/elektro/opto/ve2.dxf
/usr/share/librecad/library/elektro/opto/ve3.dxf
/usr/share/librecad/library/elektro/opto/ve4.dxf
/usr/share/librecad/library/elektro/opto/ve5.dxf
/usr/share/librecad/library/elektro/opto/ve6.dxf
/usr/share/librecad/library/elektro/opto/ve7.dxf
/usr/share/librecad/library/elektro/opto/ve8.dxf
/usr/share/librecad/library/elektro/opto/ve9.dxf