Thanks for the quick reply, laryn.
No features, no Drupal: I built the source site in Backdrop in a subdirectory of the target directory under the same user home directory on the same...
This doesn't sound right -- when the upgrade completed, did you export the post-upgrade configuration into the staging folder (and commit that to the repo if you are using a git-based workflow...
Sorry the query works.
The problem is, the global $language doesnt update unless page cache is rebuilt anytime the site language changes.
Question is why and how to fix?
Yep. Just add the 'Global: Random' Sort Criteria.