How can I fix the PDF preflight error: "The 'Widths' array in a font has an invalid length"

Question

I am trying to validate a PDF file as part of IngramSpark's pre-publishing workflow. I upload the final PDF to be published, and their software (which I believe is pdfToolbox from Callas) runs a "preflight" check on the PDF.

I get this error message: The 'Widths' array in a font has an invalid length

... but no advice on how to solve this.

Since I don't have access to pdfToolbox to run the preflight checks on my own, I have used VeraPDF (open source) to check the PDF. I am able the replicate the error in VeraPDF. When checking the PDF, VeraPDF provides a more detailed error message, as follows:

enter image description here

And here is the text of the error message:

root/document[0]/pages[0](1 0 obj PDPage)/contentStream[0](2 0 obj PDContentStream)/operators[42]/font0

Widths array is missing or has invalid size 105 instead of 106

root/document[0]/pages[1](8 0 obj PDPage)/contentStream[0](9 0 obj PDContentStream)/operators[10]/font0

Widths array is missing or has invalid size 80 instead of 81

root/document[0]/pages[11](38 0 obj PDPage)/contentStream[0](39 0 obj PDContentStream)/operators[66]/font0

Widths array is missing or has invalid size 51 instead of 52

=== end of VeraPDF error

So this error refers to a missing Widths array in two different fonts: EBGaramond-Regular (mentioned twice) and EBGaramond-Italic.

Here is what I have tried, without success:

• I have used the Google ttf (TrueType) version of these fonts: https://fonts.google.com/specimen/EB+Garamond
• I have embedded these fonts in the PDF.
• I have used the otf (OpenType) version of these fonts.
• I have Googled this error message and found a similar complaint, but without any solution: https://community.adobe.com/t5/acrobat-discussions/acrobat-preflight-reports-the-quot-widths-quot-array-in-a-font-has-an-invalid-length/td-p/11580976

Any suggestions for a fix?

Just for reference, here are possible solutions that I have pondered:

Is the missing Widths array intrinsic to the EBGaramond-Regular and EBGaramond-Italic, and therefore unfixable, so I should try a different font?

Could the font files be edited to fix the missing Widths array?

Could the PDF file be edited to fix the missing Widths array?

Have I somehow embedded the fonts improperly in the PDF?

Answer 1

This bug was introduced in LibreOffice 7.5 in https://gerrit.libreoffice.org/c/core/+/140125; and fixed in LibreOffice 7.6.2 in tdf#157112.