8 files declare their use of TextFieldMapping in FillPDF 8.4

BackendProxy.php in src/Service/BackendProxy.php

FillPdfServicePdfBackend.php in src/Plugin/PdfBackend/FillPdfServicePdfBackend.php

LegacyProviderPdfBackend.php in modules/fillpdf_legacy/src/Plugin/PdfBackend/LegacyProviderPdfBackend.php

LocalServerPdfBackend.php in src/Plugin/PdfBackend/LocalServerPdfBackend.php

PdfPopulationTest.php in tests/src/Functional/PdfPopulationTest.php

PdftkPdfBackend.php in src/Plugin/PdfBackend/PdftkPdfBackend.php

TextFieldMappingTest.php in tests/src/Unit/FieldMapping/TextFieldMappingTest.php

TokenResolver.php in src/TokenResolver.php