21 files declare their use of ProcessorInterface in Feeds 8.3

DefaultEntityProcessorForm.php in src/Feeds/Processor/Form/DefaultEntityProcessorForm.php

EntityIdTest.php in tests/src/Kernel/EntityIdTest.php

EntityReferenceTest.php in tests/src/Kernel/Feeds/Target/EntityReferenceTest.php

ExpireTest.php in tests/src/Functional/ExpireTest.php

FeedsItemTest.php in tests/src/Kernel/FeedsItemTest.php

FeedTest.php in tests/src/Kernel/Entity/FeedTest.php

FieldTest.php in tests/src/Kernel/Feeds/Target/FieldTest.php

FileTest.php in tests/src/Kernel/Feeds/Target/FileTest.php

HashTest.php in tests/src/Kernel/HashTest.php

HttpFetcherTest.php in tests/src/Functional/Feeds/Fetcher/HttpFetcherTest.php

PasswordTest.php in tests/src/Functional/Feeds/Target/PasswordTest.php

PathTest.php in tests/src/Kernel/Feeds/Target/PathTest.php

ProcessorBase.php in src/Feeds/Processor/ProcessorBase.php

SkipNewTest.php in tests/src/Kernel/SkipNewTest.php

SourcePluginsTest.php in tests/src/Kernel/SourcePluginsTest.php

TranslationTest.php in tests/src/Kernel/Feeds/Target/TranslationTest.php

UpdateExistingTest.php in tests/src/Functional/UpdateExistingTest.php

UpdateExistingTest.php in tests/src/Kernel/UpdateExistingTest.php

UpdateNonExistentTest.php in tests/src/Functional/UpdateNonExistentTest.php

UpdateNonExistentTest.php in tests/src/Kernel/UpdateNonExistentTest.php

UserRoleTest.php in tests/src/Kernel/Feeds/Target/UserRoleTest.php