Config inspector returns an error about missing config schema.
Review and validity configurations with drush:
$ drush config:inspect --detail --only-error
This message appears:
system.authorize No schema
system.rss:items.limit missing schema
system.rss:channel missing schema
Closed: outdated
9.5
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
These config items have been removed, they did actually end up having schema at some point though.
https://git.drupalcode.org/project/drupal/-/commit/cf4a6098f49e353232540...
https://git.drupalcode.org/project/drupal/-/commit/b36543da7157d48034f28...