settings.js doesn't exist. Throws 500 pg error.
While using composer to update modules and fix a library missing problem, I enabled a module called 'library manager' to view library status. It crashed with 1 error - a missing file from ExtLink. Review of the Extlink module extlink.libraries.yml indeed shows a reference to a "settings.js" file that is not located incorrectly and/or is simply missing.
Update both extlink.libraries.yml and extlink.routing.yml and extlink.routing.yml references to a placeholder file or reference a different file.
Fixed
1.0
Code
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
If a site is not in the root directory of a domain, this change will cause the path to settings.js to be incorrect (/extlink/settings.js versus /drupal_root/extlink/settings.js)
(It's also causing a downstream warning that csp.module needs to work around, but I don't expect many other modules will have the same issue: #3223558-20: Hundreds of log entries: Uninitialized string offset: 0 → )