After applying the latest dom0 update, my whonix qubes stopped updating. I see there are updates available, but when I try to apply them, they stopping at 4% and failing. All other qubes are successfully updating.
Also: my sys-whonix now always shows that it has been updated and a restart required to apply the changes. I can restart many time as I want, but looks like for now I stucked with this alert.
As a daily whonix user: help!
Can you post the update log?
When I tried to copy the log looks like that the problem just solved itself!! They are updated finally. 
Just when I started to worry. I hope that is the end of the story, thank you @apparatus for offering help!
It’s probably just a transient issue with unstable Tor connection.
Meanwhile I found a real problem though: my Tor browser in Whonix really stucked on an old version (13.0.1.). This was not connected with the dom0 update, I was suspicious from a while, because the browser was all the time saying that there is an update avaliable. A few days ago I started to monitor the version of the browser, it is the one heavily outdated one from above. After this successful update I checked again, and it is still at the same. However, I open a new topic for this as probably this is a different issue.