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We have checked the reported issue with EnableRepeatTableHeader in WebKit converter. When the EnableRepeatTableHeader property is true, HTML converter will repeat the entire header content page if table is split between pages. We could not ignore any fields inside the header content, when the page break occurs. We have attached the output PDF document for your reference. Please find the screenshot from below,
If it is not your requirement, kindly provide more details about the requirement and share us the HTML file, PDF document, code snippet et., so that it will be helpful for us to analyze and assist you further on this.