https://bugzilla.redhat.com/show_bug.cgi?id=1919639
--- Comment #27 from Robert robert.de.rooy@gmail.com --- A few answers...
Regarding the patch, I will keep it in mind for the future. Yes the patch was submitted upstream and merged.
For the .desktop and .metainfo.xml files, I have updated the spec file to do the validation and have submitted the changes upstream.
A new DOSBox-X release is due in a few days, and I will update the SRPM then. In the meantime, I have placed an updated spec file online with the changes.
https://github.com/rderooy/dosbox-x-rpm/blob/master/dosbox-x.spec