Hello mparker,
Confirming with my team, text selection is based in the PDFJS library, also noted in this forum post: PDFJSExpress vs PDFTron highlighting problem - #11 by Logan
“As mentioned, text selection is a function of the PDF.js Core library, which we do not support.”
Unfortunately we cannot fix every text selection issue in the PDFJS library, but we will add this to our backlog to look into
Best regards,
Tyler Gordon
Web Development Support Engineer
PDFTron
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