Looks like when documentetaion is build with sphinx 4.1.2 sphinx-build shows some warnings

build/BUILD/dnf-4.8.0/doc /home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/noarch-redhat-linux-gnu/doc
Running Sphinx v4.1.2
building [mo]: targets for 0 po files that are out of date
building [man]: all manpages
updating environment: [new config] 29 added, 0 changed, 0 removed
reading sources... [100%] user_faq
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:1138: WARNING: Duplicate explicit target name: "color-label".
looking for now-outdated files... none found
pickling environment... done
checking consistency... done
writing... dnf-automatic.8 { } dnf.8 { } dnf.conf.5 { } /home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:553: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:561: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:569: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:577: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:585: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:593: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:601: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:609: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:617: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:624: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:632: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:640: WARNING: undefined label: color-label
yum.conf.5 { } /home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:553: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:561: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:569: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:577: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:585: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:593: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:601: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:609: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:617: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:624: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:632: WARNING: undefined label: color-label
/home/tkloczko/rpmbuild/BUILD/dnf-4.8.0/doc/conf_ref.rst:640: WARNING: undefined label: color-label
dnf-transaction-json.5 { } yum2dnf.8 { } yum.8 { } yum-shell.8 { } yum-aliases.1 { } dnf.modularity.7 { } done
build succeeded, 25 warnings.