38 files declare their use of FieldWidget

BooleanCheckboxWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/BooleanCheckboxWidget.php
CommentWidget.php in core/modules/comment/src/Plugin/Field/FieldWidget/CommentWidget.php
DateRangeDatelistWidget.php in core/modules/datetime_range/src/Plugin/Field/FieldWidget/DateRangeDatelistWidget.php
DateRangeDefaultWidget.php in core/modules/datetime_range/src/Plugin/Field/FieldWidget/DateRangeDefaultWidget.php
DateTimeDatelistWidget.php in core/modules/datetime/src/Plugin/Field/FieldWidget/DateTimeDatelistWidget.php
DateTimeDefaultWidget.php in core/modules/datetime/src/Plugin/Field/FieldWidget/DateTimeDefaultWidget.php
DummyAjaxWidget.php in core/modules/image/tests/modules/image_module_test/src/Plugin/Field/FieldWidget/DummyAjaxWidget.php
EmailDefaultWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/EmailDefaultWidget.php
EntityReferenceAutocompleteTagsWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/EntityReferenceAutocompleteTagsWidget.php
EntityReferenceAutocompleteWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/EntityReferenceAutocompleteWidget.php
FileWidget.php in core/modules/file/src/Plugin/Field/FieldWidget/FileWidget.php
ImageWidget.php in core/modules/image/src/Plugin/Field/FieldWidget/ImageWidget.php
LanguageSelectWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/LanguageSelectWidget.php
LayoutBuilderWidget.php in core/modules/layout_builder/src/Plugin/Field/FieldWidget/LayoutBuilderWidget.php
LinkWidget.php in core/modules/link/src/Plugin/Field/FieldWidget/LinkWidget.php
MediaLibraryInceptionWidget.php in core/modules/media_library/tests/modules/media_library_test_widget/src/Plugin/Field/FieldWidget/MediaLibraryInceptionWidget.php
MediaLibraryWidget.php in core/modules/media_library/src/Plugin/Field/FieldWidget/MediaLibraryWidget.php
ModerationStateWidget.php in core/modules/content_moderation/src/Plugin/Field/FieldWidget/ModerationStateWidget.php
NumberWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/NumberWidget.php
OEmbedWidget.php in core/modules/media/src/Plugin/Field/FieldWidget/OEmbedWidget.php
OptionsButtonsWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/OptionsButtonsWidget.php
OptionsSelectWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/OptionsSelectWidget.php
PathWidget.php in core/modules/path/src/Plugin/Field/FieldWidget/PathWidget.php
ShapeOnlyColorEditableWidget.php in core/modules/system/tests/modules/entity_test/src/Plugin/Field/FieldWidget/ShapeOnlyColorEditableWidget.php
StringTextareaWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/StringTextareaWidget.php
StringTextfieldWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/StringTextfieldWidget.php
TelephoneDefaultWidget.php in core/modules/telephone/src/Plugin/Field/FieldWidget/TelephoneDefaultWidget.php
TestFieldWidget.php in core/modules/field/tests/modules/field_test/src/Plugin/Field/FieldWidget/TestFieldWidget.php
TestFieldWidgetMultilingual.php in core/modules/field/tests/modules/field_test/src/Plugin/Field/FieldWidget/TestFieldWidgetMultilingual.php
TestFieldWidgetMultiple.php in core/modules/field/tests/modules/field_test/src/Plugin/Field/FieldWidget/TestFieldWidgetMultiple.php
TestFieldWidgetMultipleSingleValues.php in core/modules/field/tests/modules/field_test/src/Plugin/Field/FieldWidget/TestFieldWidgetMultipleSingleValues.php
TestTextfieldWidget.php in core/modules/field/tests/modules/field_plugins_test/src/Plugin/Field/FieldWidget/TestTextfieldWidget.php
TextareaWidget.php in core/modules/text/src/Plugin/Field/FieldWidget/TextareaWidget.php
TextareaWithSummaryWidget.php in core/modules/text/src/Plugin/Field/FieldWidget/TextareaWithSummaryWidget.php
TextfieldWidget.php in core/modules/text/src/Plugin/Field/FieldWidget/TextfieldWidget.php
TimestampDatetimeWidget.php in core/lib/Drupal/Core/Datetime/Plugin/Field/FieldWidget/TimestampDatetimeWidget.php
UriWidget.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/UriWidget.php
WidgetPluginManager.php in core/lib/Drupal/Core/Field/WidgetPluginManager.php

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