13 files declare their use of FieldPluginBase

ContextualLinks.php in core/modules/contextual/src/Plugin/views/field/ContextualLinks.php
DblogMessage.php in core/modules/dblog/src/Plugin/views/field/DblogMessage.php
DblogOperations.php in core/modules/dblog/src/Plugin/views/field/DblogOperations.php
EntityLink.php in core/modules/comment/src/Plugin/views/field/EntityLink.php
FieldFormButtonTest.php in core/modules/views/tests/modules/views_test_data/src/Plugin/views/field/FieldFormButtonTest.php
FieldKernelTest.php in core/modules/views/tests/src/Kernel/Handler/FieldKernelTest.php
FieldPluginBaseTest.php in core/modules/views/tests/src/Unit/Plugin/field/FieldPluginBaseTest.php
Contains \Drupal\Tests\views\Unit\Plugin\field\FieldPluginBaseTest.
FieldTest.php in core/modules/views/tests/modules/views_test_data/src/Plugin/views/field/FieldTest.php
File.php in core/modules/file/src/Plugin/views/field/File.php
MediaLibrarySelectForm.php in core/modules/media_library/src/Plugin/views/field/MediaLibrarySelectForm.php
Node.php in core/modules/node/src/Plugin/views/field/Node.php
StatisticsLastCommentName.php in core/modules/comment/src/Plugin/views/field/StatisticsLastCommentName.php
UserData.php in core/modules/user/src/Plugin/views/field/UserData.php

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