Hi,ruby-thor 0.20.3 is required for rails 6 transition and was in experimental for a long time. I tested reverse dependencies today and found only ruby-coveralls is failing with this version (#956600 filed).
Out of 25 autopkgtests 25 rebuils, these were failing already: ruby-combustion ruby-librarian ruby-license-finder jquery-ui-rails.
These packages have no tests: fontcustom mhc librarian-puppet-simple sisu