27 files declare their use of FormBuilderInterface

AjaxFormBlock.php in core/modules/system/tests/modules/ajax_forms_test/src/Plugin/Block/AjaxFormBlock.php
AreaDisplayLinkTest.php in core/modules/views/tests/src/Kernel/Handler/AreaDisplayLinkTest.php
BlockListBuilder.php in core/modules/block/src/BlockListBuilder.php
DbLogController.php in core/modules/dblog/src/Controller/DbLogController.php
DisplayLink.php in core/modules/views/src/Plugin/views/area/DisplayLink.php
EntityFormBuilder.php in core/lib/Drupal/Core/Entity/EntityFormBuilder.php
EntityOperations.php in core/modules/content_moderation/src/EntityOperations.php
FileUploadForm.php in core/modules/media_library/src/Form/FileUploadForm.php
FormAjaxSubscriber.php in core/lib/Drupal/Core/Form/EventSubscriber/FormAjaxSubscriber.php
FormAjaxSubscriberTest.php in core/tests/Drupal/Tests/Core/Form/EventSubscriber/FormAjaxSubscriberTest.php
FormBuilderTest.php in core/tests/Drupal/Tests/Core/Form/FormBuilderTest.php
Contains \Drupal\Tests\Core\Form\FormBuilderTest.
FormController.php in core/lib/Drupal/Core/Controller/FormController.php
HtmlEntityFormController.php in core/lib/Drupal/Core/Entity/HtmlEntityFormController.php
HtmlFormController.php in core/lib/Drupal/Core/Controller/HtmlFormController.php
MediaLibrarySelectForm.php in core/modules/media_library/src/Plugin/views/field/MediaLibrarySelectForm.php
MediaLibraryUiBuilder.php in core/modules/media_library/src/MediaLibraryUiBuilder.php
OEmbedForm.php in core/modules/media_library/src/Form/OEmbedForm.php
PathAliasListBuilder.php in core/modules/path/src/PathAliasListBuilder.php
RedirectFormBlock.php in core/modules/system/tests/modules/form_test/src/Plugin/Block/RedirectFormBlock.php
RenderElement.php in core/lib/Drupal/Core/Render/Element/RenderElement.php
RenderElementTest.php in core/tests/Drupal/Tests/Core/Render/Element/RenderElementTest.php
SearchBlock.php in core/modules/search/src/Plugin/Block/SearchBlock.php
SystemController.php in core/modules/system/src/Controller/SystemController.php
TestFormApiFormBlock.php in core/modules/layout_builder/tests/modules/layout_builder_form_block_test/src/Plugin/Block/TestFormApiFormBlock.php
TimezoneTest.php in core/tests/Drupal/KernelTests/Core/Datetime/Element/TimezoneTest.php
ViewAjaxController.php in core/modules/views/src/Controller/ViewAjaxController.php
WorkspaceSwitcherBlock.php in core/modules/workspaces/src/Plugin/Block/WorkspaceSwitcherBlock.php

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