35 files declare their use of Condition

Access.php in core/modules/node/src/Plugin/views/filter/Access.php
AliasRepository.php in core/lib/Drupal/Core/Path/AliasRepository.php
AliasStorage.php in core/lib/Drupal/Core/Path/AliasStorage.php
BooleanOperator.php in core/modules/views/src/Plugin/views/filter/BooleanOperator.php
Condition.php in core/lib/Drupal/Core/Entity/Query/Sql/Condition.php
ConditionAggregate.php in core/lib/Drupal/Core/Entity/Query/Sql/ConditionAggregate.php
ConditionTest.php in core/tests/Drupal/Tests/Core/Database/ConditionTest.php
Connection.php in core/lib/Drupal/Core/Database/Connection.php
ConnectionTest.php in core/tests/Drupal/KernelTests/Core/Database/ConnectionTest.php
Current.php in core/modules/user/src/Plugin/views/filter/Current.php
database.inc in core/includes/database.inc
Core systems for the database layer.
DatabaseLegacyTest.php in core/tests/Drupal/KernelTests/Core/Database/DatabaseLegacyTest.php
EntityReference.php in core/modules/views/src/Plugin/views/display/EntityReference.php
File.php in core/modules/file/src/Plugin/migrate/source/d7/File.php
HelpSearch.php in core/modules/help_topics/src/Plugin/Search/HelpSearch.php
IndexTidDepth.php in core/modules/taxonomy/src/Plugin/views/argument/IndexTidDepth.php
LoggedStatementsTrait.php in core/modules/system/tests/modules/database_statement_monitoring_test/src/LoggedStatementsTrait.php
ManyToOneHelper.php in core/modules/views/src/ManyToOneHelper.php
ModerationStateFilter.php in core/modules/content_moderation/src/Plugin/views/filter/ModerationStateFilter.php
NodeGrantDatabaseStorage.php in core/modules/node/src/NodeGrantDatabaseStorage.php
NodeSearch.php in core/modules/node/src/Plugin/Search/NodeSearch.php
Search.php in core/modules/search/src/Plugin/views/filter/Search.php
Search.php in core/modules/search/src/Plugin/views/argument/Search.php
SearchIndex.php in core/modules/search/src/SearchIndex.php
SearchQuery.php in core/modules/search/src/SearchQuery.php
SelectComplexTest.php in core/tests/Drupal/KernelTests/Core/Database/SelectComplexTest.php
Sql.php in core/modules/views/src/Plugin/views/query/Sql.php
StringDatabaseStorage.php in core/modules/locale/src/StringDatabaseStorage.php
StringFilter.php in core/modules/views/src/Plugin/views/filter/StringFilter.php
TaxonomyIndexTidDepth.php in core/modules/taxonomy/src/Plugin/views/filter/TaxonomyIndexTidDepth.php
UpdateComplexTest.php in core/tests/Drupal/KernelTests/Core/Database/UpdateComplexTest.php
UserSelection.php in core/modules/user/src/Plugin/EntityReferenceSelection/UserSelection.php
UserUid.php in core/modules/comment/src/Plugin/views/argument/UserUid.php
UserUid.php in core/modules/comment/src/Plugin/views/filter/UserUid.php
ViewsSearchQuery.php in core/modules/search/src/ViewsSearchQuery.php

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