I think I have a problem with yum file configuration. Fedora 25 looks like ok but Qubes never finds data:
Fedora 25 - x86_64 - Updates 1.0 MB/s | 24 MB 00:24 Fedora 25 - x86_64 2.0 MB/s | 50 MB 00:25 Qubes Dom0 Repository (updates) 86 B/s | 169 B 00:01 Qubes Community Templates repository 84 B/s | 169 B 00:02 Qubes Templates repository 116 B/s | 169 B 00:01 Qubes Templates repository 116 B/s | 169 B 00:01 Failed to synchronize cache for repo 'qubes-dom0-current', ignoring this repo. Failed to synchronize cache for repo 'qubes-templates-sommunity', ignoring this repo. Failed to synchronize cache for repo 'qubes-templates-itl', ignoring this repo. Failed to synchronize cache for repo 'qubes-templates-itl-testing', ignoring this repo. Last metadata expiration check: 0:00:09 ago on Sun Jan 6 10:12:44 2019. Dependencies resolved. Nothing to do. Complete! No packages downloaded -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to qubes-users+unsubscr...@googlegroups.com. To post to this group, send email to qubes-users@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/7d74d653-5fa2-4d91-8ff0-62a7a8016e82%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.