6 files declare their use of PatternSourceBase in UI Patterns 8

DsFieldSource.php in modules/ui_patterns_ds/src/Plugin/UiPatterns/Source/DsFieldSource.php

DsFieldTemplateSource.php in modules/ui_patterns_ds/src/Plugin/UiPatterns/Source/DsFieldTemplateSource.php

FieldSource.php in src/Plugin/UiPatterns/Source/FieldSource.php

PatternDisplayFormTrait.php in src/Form/PatternDisplayFormTrait.php

TestSource.php in tests/modules/ui_patterns_field_source_test/src/Plugin/UiPatterns/Source/TestSource.php

ViewsRowSource.php in modules/ui_patterns_views/src/Plugin/UiPatterns/Source/ViewsRowSource.php