PDF-Lib on Vue

[mcfltimpug]

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Generate PDf

<script> import { degrees, PDFDocument, rgb, StandardFonts } from 'pdf-lib';

export default {
data: () => ({

}),
methods: {
async modifyPdf() {
const url = 'https://pdf-lib.js.org/assets/with_update_sections.pdf'
const existingPdfBytes = await fetch(url).then(res => res.arrayBuffer())

  const pdfDoc = await PDFDocument.load(existingPdfBytes)
  const helveticaFont = await pdfDoc.embedFont(StandardFonts.Helvetica)

  const pages = pdfDoc.getPages();
  const firstPage = pages[0];
  const { width, height } = firstPage.getSize()
  
  firstPage.drawText('This text was added with JavaScript!', {
    x: 5,
    y: height / 2 + 300,
    size: 50,
    font: helveticaFont,
    color: rgb(0.95, 0.1, 0.1),
    rotate: degrees(-45),
  })

  pdfBytes = await pdfDoc.save()
}

}
}
</script>

I use the above code but it's giving this error:

24:15 error 'width' is assigned a value but never used no-unused-vars
35:7 error 'pdfBytes' is not defined no-undef