The icon provider works with the Icon API, however, Icons are allowed to come back as NULL, which breaks some API implementations, as the API is not engineered for NULL results.
1. On Drupal 11.1, Install iconify_icons_provider, ui_icons, and ui_icons_library modules
2. Enable "Material Symbols" category in the in the Iconify Icons Provider module.
3. Attempt to view available libraries at /admin/appearance/ui/icons
You will receive the following:
The website encountered an unexpected error. Try again later.
TypeError: Drupal\ui_icons\IconPreview::getPreview(): Argument #1 ($icon) must be of type Drupal\Core\Theme\Icon\IconDefinitionInterface, null given, called in /var/www/html/web/modules/contrib/ui_icons/modules/ui_icons_library/src/Controller/LibraryIndex.php on line 159 in Drupal\ui_icons\IconPreview::getPreview() (line 34 of modules/contrib/ui_icons/src/IconPreview.php).
Drupal\ui_icons_library\Controller\LibraryIndex->buildCard() (Line: 108)
Drupal\ui_icons_library\Controller\LibraryIndex->index()
call_user_func_array() (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 593)
Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 121)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 183)
Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 76)
Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 53)
Drupal\Core\StackMiddleware\Session->handle() (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 28)
Drupal\Core\StackMiddleware\ContentLength->handle() (Line: 32)
Drupal\big_pipe\StackMiddleware\ContentLength->handle() (Line: 116)
Drupal\page_cache\StackMiddleware\PageCache->pass() (Line: 90)
Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 36)
Drupal\Core\StackMiddleware\AjaxPageState->handle() (Line: 51)
Drupal\Core\StackMiddleware\StackedHttpKernel->handle() (Line: 709)
Drupal\Core\DrupalKernel->handle() (Line: 19)
In testing, this is being caused by the collection id not matching the pack_id in cases there the collection id has a dash. For instance, the 'Material Line Icons" pack has a collection id of line-id, however the machinename pack_id is line_id, which causes a mismatch in Drupal/Core/Theme/Icon/IconCollector.php:86. This is derived from the passed icon_full_id via a simple explode in Drupal/Core/Theme/Icon/IconDefinition.php:88, and so does not match.
Align these to match.