When building my LiveCD I get a message about the conflict:
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Error creating Live CD : Failed to build transaction :
Problem 1: package xfce4-session-4.13.2-2.fc30.x86_64 obsoletes xfce4-session-engines <= 4.13.1 provided by xfce4-session-engines-4.13.1-23.fc30.x86_64
- cannot install the best candidate for the job
- conflicting requests
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But the xfce4-session-engines package is required to be installed on the fedora-comps description: https://pagure.io/fedora-comps/blob/master/f/comps-f30.xml.in:
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<packagereq type="mandatory">xfce4-session</packagereq>
<packagereq type="mandatory">xfce4-session-engines</packagereq>
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