/usr/share/avogadro/fragments/heteroaromatics/ is in avogadro-data 1.2.0-1+deb9u1.
This file is owned by root:root, with mode 0o755.
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/usr/share/avogadro/fragments/heteroaromatics/1H-indole.cml
/usr/share/avogadro/fragments/heteroaromatics/1H-pyrazole.cml
/usr/share/avogadro/fragments/heteroaromatics/1H-pyrrole.cml
/usr/share/avogadro/fragments/heteroaromatics/1_2-oxazole.cml
/usr/share/avogadro/fragments/heteroaromatics/1_2-thiazole.cml
/usr/share/avogadro/fragments/heteroaromatics/1_3-oxazole.cml
/usr/share/avogadro/fragments/heteroaromatics/1_3-thiazole.cml
/usr/share/avogadro/fragments/heteroaromatics/benzofuran.cml
/usr/share/avogadro/fragments/heteroaromatics/benzothiophene.cml
/usr/share/avogadro/fragments/heteroaromatics/furan.cml
/usr/share/avogadro/fragments/heteroaromatics/isonicotinamide.cml
/usr/share/avogadro/fragments/heteroaromatics/isonicotinic_acid.cml
/usr/share/avogadro/fragments/heteroaromatics/nicotinamide.cml
/usr/share/avogadro/fragments/heteroaromatics/nicotinic_acid.cml
/usr/share/avogadro/fragments/heteroaromatics/picolinamide.cml
/usr/share/avogadro/fragments/heteroaromatics/picolinic_acid.cml
/usr/share/avogadro/fragments/heteroaromatics/pyridine.cml
/usr/share/avogadro/fragments/heteroaromatics/thiophene.cml