public void setSuppressDuplicateOverlappingText(boolean suppressDuplicateOverlappingText) {
        this.suppressDuplicateOverlappingText = suppressDuplicateOverlappingText;
        userConfigured.add("suppressDuplicateOverlappingText");
    }
If true, the parser should try to remove duplicated
text over the same region.  This is needed for some
PDFs that achieve bolding by re-writing the same
text in the same area.  Note that this can
slow down extraction substantially (PDFBOX-956) and
sometimes remove characters that were not in fact
duplicated (PDFBOX-1155).  By default this is disabled.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-pdf-module/src/main/java/org/apache/tika/parser/pdf/PDFParserConfig.java