906379 - Some textual web pages printed as images

Status: RESOLVED FIXED

(Core :: Printing: Output, defect, P4)

Description

[Joe Smith]

GENERAL ISSUE DESCRIPTION:
-----------------------------
Some websites, when printed to PDF, are printed as images. That results in the related handicaps, such as:
- Text of the printed PDF document cannot be selected
- The printed PDF document is of very bad quality (due to image compression), with smaller text almost unreadable
- The file size of the printed PDF document is larger that one of a text-based PDF file

The issue occurs only on some web sites/pages, such as e.g. following:
- http://docs.joomla.org/Customising_the_dynamic_page_title
- http://hunyadi.info.hu/levente/en/sigplus/documentation

I am reporting the issue with the FF release 23.0 I currently use, but the issue actually first occurred one of earlier versions. My guess would be somewhere between versions 20 and 22. I just have not found time to report it. So, this is a regression.

I am using the "PDFCreator" PDF printer in its version 1.2.3 - which is already a few years old. But don't think the issue is with the printer, because:
- I have used that same version for a few years now, also with earlier FF versions where the issue reported here did not occur.
- The issue does not occur when the affected web page is printed to PDF from Internet Explorer 8 on the same machine.
- While I am not an expert, it seems that the issue can also be observed when a web site is printed to a file ("print to file") instead to a PDF (i.e. without using the above PDF printer). The resulting file, when opened with a text editor, seems to also contain an image of the page. (And the page text cannot be found in it, while found in the "print to file" output of IE8.)


TEST PROCEDURE:
----------------
1) Open one of the above affected pages
2) Go to the menu File -> Page Preview
3) Click the "Print" button, select the PDF (virtual) printer (or alternatively "print to file", as described above) and print to a PDF document
4) Open the printed PDF document with a PDF reader (I use PDF-XChange Viewer) and try selecting some text within the document


EXPECTED RESULTS:
-------------------
4) Text can be selected


ACTUAL RESULTS:
-------------------
4) Text cannot be selected. Also, the document quality is very poor (small print hardly readable) while the file size is significantly larger than that of a text-based PDF file. (Compared to the PDF print-out of the same page printed on a FF version before the regression.)



FF configuration info (from the Info -> ... menu), German version (not a very space-efficient output compared to earlier FF versions, by the way):
------------------------------------------------------------------

  Allgemeine Informationen

        Name
        Firefox

        Version
        23.0

        User-Agent
        Mozilla/5.0 (Windows NT 5.1; rv:23.0) Gecko/20100101 Firefox/23.0

        Build-Konfiguration

          about:buildconfig

  Erweiterungen

        Name

        Version

        Aktiviert

        ID

        Microsoft .NET Framework Assistant
        0.0.0
        false
        {20a82645-c095-46ed-80e3-08825760534b}

  Wichtige modifizierte Einstellungen

      Name

      Wert

        accessibility.typeaheadfind.flashBar
        0

        browser.cache.disk.capacity
        1048576

        browser.cache.disk.smart_size.first_run
        false

        browser.cache.disk.smart_size_cached_value
        819200

        browser.places.smartBookmarksVersion
        4

        browser.search.update
        false

        browser.startup.homepage_override.buildID
        20130730113002

        browser.startup.homepage_override.mstone
        ignore

        dom.mozApps.used
        true

        dom.w3c_touch_events.expose
        false

        extensions.lastAppVersion
        23.0

        gfx.blacklist.suggested-driver-version
        6.14.10.5260

        media.navigator.enabled
        false

        network.cookie.lifetimePolicy
        2

        network.cookie.prefsMigrated
        true

        places.database.lastMaintenance
        1376013995

        places.history.expiration.transient_current_max_pages
        26585

        plugin.disable_full_page_plugin_for_types
        application/pdf

        plugin.importedState
        true

        plugin.state.npdrmv
        0

        plugin.state.npdsplay
        0

        plugin.state.npwmsdrm
        0

        plugin.state.npwpf
        0

        plugins.hide_infobar_for_missing_plugin
        true

        plugins.notifyMissingFlash
        false

        privacy.clearOnShutdown.offlineApps
        true

        privacy.clearOnShutdown.passwords
        true

        privacy.cpd.cookies
        false

        privacy.cpd.downloads
        false

        privacy.cpd.history
        false

        privacy.cpd.offlineApps
        true

        privacy.cpd.sessions
        false

        privacy.sanitize.migrateFx3Prefs
        true

        privacy.sanitize.sanitizeOnShutdown
        true

        security.warn_viewing_mixed
        false

        storage.vacuum.last.index
        0

        storage.vacuum.last.places.sqlite
        1376014062

  Grafik

        Direct2D aktiviert
        Wurde auf Grund Ihrer Grafiktreiberversion blockiert. Versuchen Sie, Ihren Grafiktreiber auf mindestens Version 6.14.10.5260 zu aktualisieren.

        DirectWrite aktiviert
        false (0.0.0.0)

        Geräte-ID
        0xa011

        GPU #2 aktiv
        false

        GPU-beschleunigte Fenster
        0/1 Basic

        Karten-Beschreibung
        Intel(R) Graphics Media Accelerator 3150

        Karten-RAM
        Unknown

        Karten-Treiber
        igxprd32

        Treiber-Datum
        9-24-2009

        Treiber-Version
        6.14.10.5134

        Vendor-ID
        0x8086

        WebGL-Renderer
        Google Inc. -- ANGLE (Intel(R) Graphics Media Accelerator 3150)

        AzureCanvasBackend
        skia

        AzureContentBackend
        none

        AzureFallbackCanvasBackend
        cairo

  JavaScript

        Inkrementelle GC
        true

  Barrierefreiheit

        Aktiviert
        false

        Barrierefreiheit verhindern
        0

  Bibliotheken-Versionen

        Minimal vorausgesetzte Version

        Verwendete Version

        NSPR
        4.10
        4.10

        NSS
        3.15 Basic ECC
        3.15 Basic ECC

        NSSSMIME
        3.15 Basic ECC
        3.15 Basic ECC

        NSSSSL
        3.15 Basic ECC
        3.15 Basic ECC

        NSSUTIL
        3.15
        3.15

Comment 1

[Alice0775 White]

Attachment: testcase.html

If specified box-shadow, the page will print as image.

Comment 2

[Loic]

Is this a real regression?

Comment 3

[Alice0775 White]

No, it is not a regression.
The problem is exists since Firefox3.5(-moz-box-shadow implemented).

Comment 4

[Joe Smith]

Thank you for the quick analysis. I can confirm the issue using the test case you attached.

Sorry for the "regression" keyword. I'm removing it. It must be a change of the web sites (e.g. implementing "box-shadow" with a newer Joomla CMS version) that made the issue appear to me, not a Firefox version change.

Unfortunately, I can't change the bug status to "NEW" - I don't have the necessary rights.

Comment 6

[Mats Palmgren (inactive)]

WFM, Nightly 27.0a1 (2013-10-19) on Linux64, so I'm guessing this is a platform parity bug.

Comment 7

[Thomas Stein]

Hmm, I don't think it is a (only) because of box-shadow. When I disable option

"Shrink to fit page width"

then everything works fine despite the included box-shadow!

So there must be something else/more which prevents text creation (for the last page).

Comment 8

[Loic]

The underlying issue is Firefox prints box-shadowed elements as image.
In addition, no need to have many pages to make the issue appear, only one page or line is enough.

Comment 9

[Joe Smith]

I don't know if it's platform or Firefox version dependent, but the bug status is as follows in Linux Mint 17.1 (based on Ubuntu 14.04), 64 bit, FF 40.0 (as provided by the distribution):

Neither the attached testcase, nor the test pages in the bug description are printed as images (although the hunyadi.info.hu one does seem to come with an additional blank image, for whatever reason).

But following is printed as both, text and image: https://www.reddit.com/r/netsec/comments/3gklvw/remote_car_hacking_by_charlie_miller_and_chris/
Or seemingly any other comments page on https://www.reddit.com/r/netsec/

Comment 10

[Joe Smith]

(In reply to Joe Smith from comment #9)
> I don't know if it's platform or Firefox version dependent, but the bug
> status is as follows in Linux Mint 17.1 (based on Ubuntu 14.04), 64 bit, FF
> 40.0 (as provided by the distribution):
> 
> Neither the attached testcase, nor the test pages in the bug description are
> printed as images (although the hunyadi.info.hu one does seem to come with
> an additional blank image, for whatever reason).
> 
> But following is printed as both, text and image:
> https://www.reddit.com/r/netsec/comments/3gklvw/
> remote_car_hacking_by_charlie_miller_and_chris/
> Or seemingly any other comments page on https://www.reddit.com/r/netsec/

P.S.: The test was done by printing to PDF, using (1) the "Print to File" functionality coming with the distribution and (2) using another Cairo and Ghostscript based "PDF printer".

Comment 11

[Thomas Stein]

Interestingly the used font seems to play a role.

Assume I encounter such a problematic web page.
I inspect now the html/CSS code with a plugin like Firebug and replace the used font with a font like "Verdana".
Then I print the page again.....and it works now.

This workaround is not always but oftentimes a weired solution.

Comment 12

[Loic]

Fix range:
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=d45440221297&tochange=d4c4ce7f060c

I think it has been fixed by the change about drawing box-shadow:
Mason Chang — Bug 1155828 - Draw box-shadows using an approach inspired by border-image. r=mstange

Comment 13

[Thomas Stein]

It is NOT fixed!

Years ago I bookmarked the following sample page (from german computer magazin) for evaluating if it is fixed:

http://www.computerwoche.de/a/print/der-fat-client-feiert-seine-wiederkehr,546826

When I print this page then I can NOT select text in the resulting PDF document.

So the state should be "currently unfixed"

Comment 14

[Loic]

(In reply to Thomas Stein from comment #13)
> It is NOT fixed!
> 
> Years ago I bookmarked the following sample page (from german computer
> magazin) for evaluating if it is fixed:
> 
> http://www.computerwoche.de/a/print/der-fat-client-feiert-seine-wiederkehr,
> 546826
> 
> When I print this page then I can NOT select text in the resulting PDF
> document.
> 
> So the state should be "currently unfixed"

The issue is different, it's about the use of font, not box-shadow (like the testcase). I'll open a new bug report.

Comment 15

[Loic]

Filed bug 1343882.

Comment 16

[Thomas Stein]

Any progress on this issue?