12 files declare their use of WizardPluginBase in Drupal 9

BlockContent.php in core/modules/block_content/src/Plugin/views/wizard/BlockContent.php

Comment.php in core/modules/comment/src/Plugin/views/wizard/Comment.php

File.php in core/modules/file/src/Plugin/views/wizard/File.php

Media.php in core/modules/media/src/Plugin/views/wizard/Media.php

MediaRevision.php in core/modules/media/src/Plugin/views/wizard/MediaRevision.php

Node.php in core/modules/node/src/Plugin/views/wizard/Node.php

NodeRevision.php in core/modules/node/src/Plugin/views/wizard/NodeRevision.php

TaxonomyTerm.php in core/modules/taxonomy/src/Plugin/views/wizard/TaxonomyTerm.php

Users.php in core/modules/user/src/Plugin/views/wizard/Users.php

ViewAddForm.php in core/modules/views_ui/src/ViewAddForm.php

Watchdog.php in core/modules/dblog/src/Plugin/views/wizard/Watchdog.php

WizardPluginBaseTest.php in core/modules/views/tests/src/Unit/WizardPluginBaseTest.php