REQUIREMENT_WARNING

DbUpdateController::handle in core/modules/system/src/Controller/DbUpdateController.php

Returns a database update page.

DbUpdateController::requirements in core/modules/system/src/Controller/DbUpdateController.php

Renders a list of requirement errors or warnings.

demo_umami_requirements in core/profiles/demo_umami/demo_umami.install

Implements hook_requirements().

drupal_requirements_url in core/includes/install.inc

Returns a URL for proceeding to the next page after a requirements problem.

GDToolkit::getRequirements in core/modules/system/src/Plugin/ImageToolkit/GDToolkit.php

Gets toolkit requirements in a format suitable for hook_requirements().

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