A "Book name" plugin shows as a plugin that you can enable on the module's configuration page, even when the book module is not installed. If you enable it, then the sitemap displays a WSOD.
10.1.x).composer require "drupal/sitemap:2.x-dev@dev"/admin/modules. Note that the Core -> Book module is unchecked (uninstalled). Leave it that way./admin/modules. Check the checkbox next to Other -> Sitemap to install it, then click "Install"./admin/config/search/sitemap. Note under Enabled plugins, there is a "Book name" checkbox. Check it, and click "Save configuration". You see the message "The configuration options have been saved"/sitemap. You see a WSOD, or the message "The website encountered an unexpected error. Please try again later." In the dblog, you see a php message: Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException: You have requested a non-existent service "book.manager". in Drupal\Component\DependencyInjection\Container->get() (line 157 of /app/web/core/lib/Drupal/Component/DependencyInjection/Container.php)./admin/modules. Check the checkbox next to Core -> Book to install it, then click "Install"./sitemap. You see the sitemap again, but not a "Book name" section./admin/config/search/sitemap. Note under Enabled plugins, the "Book name" plugin has disappeared.Don't display plugins if the module they depend on is not installed.
Plugins will no longer display if the module that they depend on is not installed.
To be determined.
To be determined.
Closed: duplicate
2.0
Code
I just discovered that @smustgrave has posted a patch for an issue that sounds similar in 🐛 Hide books, vocabularies from settings form if modules are not enabled. Needs review
Marking as a duplicate of 🐛 Hide books, vocabularies from settings form if modules are not enabled. Needs review , will transfer parts of the issue summary over there.