Please branch and build texlive-mhchem in epel9
it is fixed in texlive-extension-20200406-33.el9
FEDORA-EPEL-2023-3fe8ed82c2 has been submitted as an update to Fedora EPEL 9. https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2023-3fe8ed82c2
FEDORA-EPEL-2023-3fe8ed82c2 has been pushed to the Fedora EPEL 9 testing repository.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2023-3fe8ed82c2
See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.
FEDORA-EPEL-2023-3fe8ed82c2 has been pushed to the Fedora EPEL 9 stable repository.
If problem still persists, please make note of it in this bug report.