1791191 - Firefox 104.* renders PDF text incorrectly on windows

Status: RESOLVED FIXED

(Firefox :: PDF Viewer, defect, P1)

Description

[reinhard.nissl]

Attachment: bad.pdf

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:104.0) Gecko/20100101 Firefox/104.0

Steps to reproduce:

Open bad.pdf

Actual results:

No text is displayed compared to good.pdf

Expected results:

bad.pdf should look like good.pdf, i. e. display "Lohnabrechnung"

Comment 1

[reinhard.nissl]

Attachment: good.pdf

Comment 2

[reinhard.nissl]

See also https://bugs.ghostscript.com/show_bug.cgi?id=705872

Comment 3

[reinhard.nissl]

Attachment: old.pdf

Provided old.pdf, mentionend in ghostscript ticket.

Comment 4

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::PDF Viewer' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 5

[reinhard.nissl]

With browser.display.use_document_fonts = 0 (as mentioned in https://bugzilla.mozilla.org/show_bug.cgi?id=1776543), the text gets displayed.

Comment 7

[Calixte Denizet (:calixte)]

I reopen this bug in order to track the fix we made in pdf.js.

Comment 8

[Calixte Denizet (:calixte)]

Attachment: PR 15900: Set ExpansionFactor to 0.06 when it's equals to 0 in the private dict of CFF fonts

Comment 10

[Calixte Denizet (:calixte)]

Comment on attachment 9311200 [details] [review]
PR 15900: Set ExpansionFactor to 0.06 when it's equals to 0 in the private dict of CFF fonts

ESR Uplift Approval Request

• If this is not a sec:{high,crit} bug, please state case for ESR consideration: According the number of duplicates we've on gh and bugzilla and since it makes some pdf impossible to read, it's probably worth having the fix in ESR.
• User impact if declined: Impossible to read some pdfs.
• Fix Landed on Version: 110
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): It's a one-line patch, pdf.js is self-contained in m-c and it's has been verified with several pdfs.

Comment 11

[Calixte Denizet (:calixte)]

Attachment: Bug 1791191 - Some pdfs are not visible on Windows because of bad ExpansionFactor in CFF fonts r=#pdfjs-reviewers,RyanVM

In such a case The ExpansionFactor is set to 0.06 (default value) when the font is converted
into an OpenType one.

Comment 12

[Ryan VanderMeulen [:RyanVM]]

Comment on attachment 9311330 [details]
Bug 1791191 - Some pdfs are not visible on Windows because of bad ExpansionFactor in CFF fonts r=#pdfjs-reviewers,RyanVM

Approved for 102.7esr.

Comment 13

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-esr102/rev/cff83fd04112

Comment 14

[Catalin Sasca, Desktop Test Engineering [:csasca]]

Reproduced the issue on Firefox 106.0a1 (2022-09-16) under Windows 10 by using the PDF provided in Comment 0.

The issue is fixed on Firefox 102.7.0esr on the same system.

Comment 15

[reinhard.nissl]

I've talked with GhostScript developers about 'bad ExpansionFactor in CFF fonts'.
They'll try to avoid creating such fonts accidentially in future.
See https://bugs.ghostscript.com/show_bug.cgi?id=705872#c6.