https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Icon_Cache
%post /bin/touch --no-create %{_datadir}/icons/hicolor &>/dev/null || :
%postun if [ $1 -eq 0 ] ; then /bin/touch --no-create %{_datadir}/icons/hicolor &>/dev/null /usr/bin/gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || : fi
%posttrans /usr/bin/gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
Somebody with write-access to that page, please add the missing " || :" to the end of the /bin/touch line in the %postun scriptlet.
Then the code would be consistent with its explanation on the page.