I just went to yumex and put chromium in it comes back with chromium, chromium-libs, chromium-pepper-flash, and chromium-widevinecdm-plugin all show '@System' under repo though but this may have come from Unitedrpms. I've got all the fedora repos and rpm repos, handbrake, folkswithhats (fedy), - I did have unitedrpms but had disabled that and it shows coming from @system - still maybe it came from that repo. https://unitedrpms.github.io/