If you already have an old d8 database, and you mistakenly specify that database during the install, the installer says "Drupal already installed" even if it isn't. I'm not sure if there's a way Drupal could distinguish between situations where the specified database exists and contains Drupal data, but the site is not actually installed, and situations where the database is set up and Drupal has been successfully installed. If it's possible to make that distinction, the "Drupal already installed" heading could be changed to something more helpful, like "You specified a database that already contains Drupal data. To continue with the install, you need to delete or empty that database, or specify a different database."
Granted, the bullets below the heading should help with that, but the heading itself can cause confusion.
Postponed: needs info
11.0 🔥
install system
Makes Drupal easier to use. Preferred over UX, D7UX, etc.
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
There hasn't been any discussion here for 4 years so perhaps this is no longer a problem?
This does need steps to reproduce, so tagging. Since we need more information to move forward with this issue, I am setting the status to Postponed (maintainer needs more info). If we don't receive additional information to help with the issue, it may be closed after three months.
Thanks!