Platform/Layout/Printing and fragmentation

This page provides information about our efforts in 2020 to improve the platform parts of printing and fragmentation in Firefox. Given how closely linked the frondend and platform parts of printing are, this will inevitably involve some frontend work too.

Rationale

Support for printing in Firefox has historically been poorly maintained, and is currently in a dismal state compared to other browsers. There are two main areas for improvement:

• Printing UX: Firefox’s printing UI/UX lacks consistency and is complicated and confusing compared to the competition. Print settings are displayed differently across operating systems, different methods of accessing printing lead to different dialogs, and print preview is not displayed by default on macOS.
• Printing output: There is a significantly-sized backlog of user-reported bugs related to print output (for both printing devices and PDF export). Some of these bugs include cases where printing fails completely, several pages are missing, or the printed layout is just incorrect.

Managing bug lists

The tables of bugs below are managed automatically using the `whiteboard` field in bugzilla.

• Add "[print2020]" to add a bug to the printing backlog
• Add "[frag2020]" to add a bug to the fragmentation backlog
• Add "[print_v{XX}]" to add a bug to the list of printing bugs targetted at Firefox vXX (e.g. "[print_v73]").
• Add "[frag_v{XX}]" to add a bug to the list of fragmentation bugs targetted at Firefox vXX (e.g. "[frag_v73]").

NIGHTLY 76

Merge to beta: 2020-04-06 (start: 2020-03-09; freeze: 2020-04-02; release: 2020-05-05)

Fragmentation

No results.

0 Total; 0 Open (0%); 0 Resolved (0%); 0 Verified (0%);

Printing

No results.

0 Total; 0 Open (0%); 0 Resolved (0%); 0 Verified (0%);

BACKLOG

Fragmentation

Full Query

ID	Summary	Assigned to	Status	Resolution
179135	top:auto blocks with position:absolute misplaced when printing		NEW
939897	[meta] Support shifting / splitting flex items between continuations of a fragmented flex container (flexbox content truncated when printing)		NEW
1157012	position:fixed element is missing on the first page in Print Preview when styled with downloadable font		NEW
1250348	Tall <iframe> elements are truncated at page boundaries (instead of being split across pages, like tall images are)		NEW
1318856	when printing a tall image (or SVG graphic), it is truncated rather than split across pages		NEW
1468369	abs.pos. element immediately after a forced page break does not render		NEW
1569436	Butterick’s Practical Typography doesn't print to PDF correctly (abspos hypothetical position on non-first page not working properly)		NEW
1633936	Add telemetry to determine how much content is clipped during printing		NEW
1648903	Printing A4 pages with abspos precisely-measured abspos content is faulty		NEW
1674682	Content overlap when fragmenting with fixed height content		UNCONFIRMED
1680728	Yahoo search page background-image is shifted/clipped in Print Preview, if WebRender is enabled (with "background-attachment: fixed")		NEW
1681079	Print preview should override the position of right aligned page elements on print selection		NEW
1648947	Broken print output from Yahoo Mail, because element with "display:table" doesn't print correctly - initial blank pages, missing content, and content that runs off the page	Ting-Yu Lin [:TYLin] (PDT, UTC-7)	RESOLVED	FIXED
1674774	Pagination/printing is quite broken for display:flex content in vertical-rl writing mode	Ting-Yu Lin [:TYLin] (PDT, UTC-7)	VERIFIED	FIXED
1665214	When "slicing" printing-improvement preserves overflow from a clipped line-box or grid row, shift down the line or grid row on the next page to leave space for the expected overflow	Mats Palmgren (inactive)	RESOLVED	FIXED
1640197	Investigate implementation of fallback "slicing" fragmentation using display list	Miko Mynttinen	RESOLVED	FIXED
1417615	[Layout] Content truncated when printing a page containing a CSS grid with large row		RESOLVED	FIXED
1344992	Lost printing content if specify the position:absolute and transform style.		RESOLVED	INVALID
649802	Abspos with margin gets progressively skinnier on each printed page		RESOLVED	DUPLICATE
1479119	Long images cut off after first page when printing		RESOLVED	DUPLICATE
1520749	Fails to print all slides from Remark.js slideshow		RESOLVED	DUPLICATE
1606540	printing problem when fragmenting tables		RESOLVED	DUPLICATE
267029	Absolutely positioned elements all print on first page, and the ones that don't fit aren't shown		RESOLVED	WORKSFORME
376033	Printing a long SVG document only prints first page		RESOLVED	WORKSFORME
1574684	www.specsavers.co.uk doesn't fully print		RESOLVED	INCOMPLETE

25 Total; 12 Open (48%); 12 Resolved (48%); 1 Verified (4%);

Printing

Full Query

ID	Summary	Assigned to	Status	Resolution
1660885	Make nsIPrinterList::GetNamedOrDefaultPrinter always return a printer, if any are available	Emily McDonough [:alaskanemily]	ASSIGNED
1660905	Add nsIPrinter::CheckConnection to determine if a printer can be reached	Emily McDonough [:alaskanemily]	ASSIGNED
1662471	Pref `print.always_print_silent` sometimes silently does nothing	Emilio Cobos Álvarez (:emilio)	ASSIGNED
1663290	Consider making afterprint event fire after spinning the event loop	Emilio Cobos Álvarez (:emilio)	NEW
1645272	[meta] Migrate our in-tree reftest-paged reftests into wpt	Hiroyuki Ikezoe (:hiro)	ASSIGNED
1664415	Unexpected title for error-message dialog on a Print operation	Jonathan Kew [:jfkthame]	ASSIGNED
1621136	Write some firefox-source-docs.mozilla.org documentation for printing	Jonathan Watt [:jwatt]	ASSIGNED
1663712	Explore fetching and caching printer information before users initiate printing	Mark Striemer [:mstriemer]	ASSIGNED
231068	new Page Header or Footer Option -- just Date (no Time)		NEW
659715	Consider preserving scroll position of iframes & other scrolled regions when printing		NEW
1249214	Scale canvas passed to mozPrintCallback to match printer resolution		NEW
1328072	[UX] [e10s] print preview opens print preview instead of showing alert like non-e10s (if printer was't found)		NEW
1444078	Printing to 300x600 dpi label printer is half width		UNCONFIRMED
1569247	[meta] Adding new telemetry printing-related probes		NEW
1615908	Consider saving only one set of print settings (instead of per-printer settings)		NEW
1622017	vh & vw units are too large (and depend on DPI), in printed / print-previewed documents		NEW
1631440	[meta] Platform support for the new print preview design		NEW
1632275	Print to PDF should add the file to the Downloads list, otherwise these file are very hard for users to find		NEW
1639844	Provide access to the native printer resolution through nsIPaper		NEW
1640533	Audit whether MOZ_CAN_RUN_SCRIPT annotations for nsPrintJob functions are correct/necessary or not		NEW
1650176	Printing a video should capture the current playing frame		NEW
1651112	[meta] Expose printer specific information using nsIPrinterList and nsIPrinter to support the new printing UI		NEW
1651654	Black pages on Print preview for icq.com page		NEW
1654497	"Cannot print this document yet..." dialog no longer appears, when printing mid load.		NEW
1657489	Zooming print preview in new print UI flickers, clamps at 100%		NEW
1657896	Print selection from BBC articles is sometimes missing the first letter of the selection		NEW
1657906	Text is displayed as cut-off in both print preview and print job's output for a specific bbc article		NEW
1657973	Support generation of tagged (accessible) PDFs		NEW
1658076	Add collation support to nsIPrintSettings		NEW
1658285	Print preview gets closed if the tab is moved to a new window		NEW
1658394	Add per-paper-size duplex information for CUPS printers		NEW
1658414	Print sheet does not have a way to add a printer		NEW
1658446	print preview: 'Scale' value should be shown/labeled as percentage ['%']		NEW
1658558	[ARM] Pages with various formats are not printed completely (several letters are arbitrarily missing)		NEW
1660468	[RTL] When a scrollbar is present in new Print UI options sidebar, changing an option from a dropdown will cause the next clicked dropdowns to appear misaligned with their `select`		NEW
1660474	Table border in Print Preview cut-off when window is narrower		NEW
1660520	Setting margins to 0.1 actually sets them to 0.100000001490116 (at least on Windows)		NEW
1660638	Please provide feature of Zoom-In/Out and tool button for print image in new print preview dialog		NEW
1660929	Prepopulate the system print dialog with all settings selected in the tab modal print preview doorhanger		NEW
1660997	Deduplicate out common code in nsPrintSettingsWin::InitWithInitializer and nsPrintSettingsWin::CopyFromNative		NEW
1661121	Linked tiles at https://www.mozilla.org/en-US/ can be hovered / dragged *in print preview mode*		NEW
1661294	Retrieve Native Resolution (DPI/PPI) Information For nsIPrinter		NEW
1661623	Text with high contrast mode in print preview is hard to read		NEW
1661691	ctrl+wheel zoom on print preview is unreliable		NEW
1661719	Changes made inside the new Print modal are kept for the old UI as well		NEW
1662239	Multiple redundant paper size entries returned in the paperList		NEW
1662302	Assertion failure: child->IsDocument(), at src/dom/base/Document.cpp:12176		NEW
1662367	print preview shouldn't reuse previously used page format for PDFs, initially always portrait used, even for landscape PDFs		NEW
1662373	Print Preview of PDF - swapping to landscape mode shows only part of a page		NEW
1662534	Headers/footers don't appear when saving to PDF with margins set to None		NEW
1662626	Investigate whether the platform printing code is compatible with scaling > 100%		NEW
1662786	No longer have the ability to cancel or monitor print progress (Implement some sort of print queue user interface)		NEW
1662934	Investigate if there is a better way to fix double-scaled printing on macOS		NEW
1663005	If "save to pdf" is selected printer, try to copy over as many current settings as possible to the system dialog.		NEW
1663623	Assertion failure: !chan (Why is there a document channel?), at toolkit/components/windowwatcher/nsWindowWatcher.cpp:1016		NEW
1663672	Print preview is blurry with a certain configuration		NEW
1663702	Make nsFrameLoader::Print support cancellation and progress reporting		NEW
1663753	Add telemetry to measure the time platform printing code takes to create/update/scroll print/preview documents		NEW
1664253	Try not creating a PrintTarget for print preview.		NEW
1664469	Get rid of nsPrintData		NEW
1664782	Return the paper list directly from nsPrinterListBase::GetFallbackPaperList without using a Promise		NEW
1664860	The footer is cut off in Landscape mode when on paper on Windows 7 (with specific printers)		NEW
1665819	Assertion failure: FirstContinuationOrPartOfIBSplit(parent) == aParent || (parent->Style()->IsInheritingAnonBox() && parent->GetContent() == aParent->GetContent()), at /builds/worker/checkouts/gecko/layout/base/RestyleManager.cpp:2110		NEW
1665830	Assertion failure: false (MOZ_ASSERT_UNREACHABLE: Why is there no non-anonymous descendants in the continuation chain?), at /builds/worker/checkouts/gecko/layout/generic/nsContainerFrame.cpp:2114		NEW
1665837	Button-text on network error pages is hard to read (dark-on-dark) when printed		NEW
1666937	Lazily add mDNS/Bonjour/Avahi printers to the print UI on CUPS platforms (missing printers)		NEW
1667260	Document exactly what settings the nsIPrintSettings returned by nsIPrinter.createDefaultSettings has set		NEW
1668043	It should not be possible to interact with the tab content (e.g. using find-in-page) while tab-modal Print UI is open		NEW
1668072	opening print dialog opens it behind already open HTTP auth prompt, should be on top		NEW
1668208	Save to PDF's print preview cuts off content in vertical frames test page		NEW
1668400	Optimization: avoid needless reflow for page-range changes		NEW
1668453	Scroll print preview on PgUp/PgDown/Home/End when they would otherwise do nothing		NEW
1668769	User can interact with some links in print preview		NEW
1668813	On Ubuntu, the Color Mode dropdown is not locked to Black&White for B&W printers		NEW
1668855	ctrl + +/- zooms the underlying page, not print preview		NEW
1669263	Sometimes, tab-modal Print Preview briefly flashes a higher-zoom version of the document, when you've made a small change to a print setting		NEW
1669329	[mac] Scaling value is not reflected in native print dialog		NEW
1669385	Replace nsIPrintSettings.paperWidth/paperHeight/paperSizeUnit with a single setter		NEW
1669467	Print preview - tapping left-right should select between Portrait-Landscape options instead of scrolling between the options		NEW
1669469	No draggable action should be allowed in print preview		NEW
1669647	The background of a certain iframe is not steady in Print preview		NEW
1669699	Space height inconsistency after error messages inside the new Print modal		NEW
1669762	Rename some attributes in nsIWebBrowserPrint.idl with s/page/sheet/		NEW
1669904	Stop using PrintUtils.getPrintSettings in the new printing UI		NEW
1669910	Firefox draws the header/footer at the extreme edge of writeable area, which can lead to clipped header/footer in some situations (e.g. if printer lies about printable region, or if user prints to PDF and then prints that PDF to a physical printer)		NEW
1695647	Printing to a paused printer on macOS silently does nothing		NEW
1670037	Get rid of the DeferredTask code in print.js		NEW
1670110	Consider moving the "Paper size" field outside the collapsed-by-default "More settings" section		NEW
1670135	Add user interface to allow users to collate their printouts when printing multiple copies		NEW
1670287	Elements not supported by Cairo appear in Print Preview despite not appearing in Print output		NEW
1670638	[Reader View] Borders are not displayed in print preview		NEW
1695552	macOS Printer Status Icon		NEW
1693989	PDF content gets clipped when printing, if it's too close to page edge (with no way to shrink to fit printable area)		NEW
1670887	Print selection (context menu) images on some of the top sites are broken in print preview		NEW
1670912	[macOS] Increase/Decrease buttons are different in Print Preview		NEW
1691420	Consider making the preview have initial focus instead of the destination.		NEW
1691381	The paginator’s “first page” and “last page” buttons extremities are transparent when shrinking the browser window		NEW
1673908	Overextended Paper size dropdown at fullscreen exit for Foxit option (version <10 )		NEW
1688597	Canceling the file picker while printing an about local page locally blocks the print preview in a “Printing…” state		NEW
1674365	Improve print preview for printers with very long potential pages, for example receipt printers.		NEW
1685476	Print selection via context menu & via the new modal is not reflected inside the system dialog		NEW
1675462	Print preview - Swapping from Scale to Fit To page and repeating with invalid scale should reset to previous valid value instead of 100		NEW
1675474	Two OS print modals can be triggered at the same time		NEW
1684952	Print jobs with complex print ranges will always print the pages in ascending order, even if the user's range has them in some other order		NEW
1676422	Excite's page background is offset in Print Preview (2018 regression)		NEW
1676828	[macOS 11] Default printer settings are different than of the other os's		NEW
1677327	Add 'Save PDF' option in modal print dialog on macOS		NEW
1683317	Output copies are doubled for a specific document		NEW
1678586	The Selection radio button from the system dialog panel is disabled if the system dialog was opened before the print preview finished loading		NEW
1678982	Clicking in the middle of the Scale arrows increases the scale while having a caret displayed		NEW
1678983	Print Preview - disable scale carets when values reach max or min values accordingly		NEW
1679041	Firefox doesn't allow page layout area to be inflated with negative @page margins		NEW
1679123	[mac] Print preview - focus ring shown in preview on part of page		NEW
1679153	Buttons from about:sessionrestore disappear when deselecting Print Backgrounds in Print Preview		NEW
1679389	Max scale values are different between new and system modal		NEW
1785279	Combine mCreatedForPrintPreview, mIsDoingPrinting and mIsCreatingPrintPreview		NEW
1679397	Print preview repainting at small scales looks fuzzy		NEW
1681908	Print Preview - adjust sheet indicator focus ring so it doesn't falsely show as being of a bigger size than button/needed		NEW
1679514	The background image has a really low quality when the "Save to PDF" option is used		NEW
1679515	Low Ink/toner levels notification should be displayed on the new modal as well		NEW
1681284	Some animations are played inside the Print preview		NEW
1680153	Scrolling is janky with the pages per sheet option		NEW
1680728	Yahoo search page background-image is shifted/clipped in Print Preview, if WebRender is enabled (with "background-attachment: fixed")		NEW
1681110	Print preview displays a blank page for fr.calameo.com previews at first try		NEW
1681206	@page margin:0 seems to be special and does not behave the same as margin:0.01px w.r.t. non-printable areas		NEW
1660223	Crash in [@ gtk_printer_get_name]	Daniel Holbert [:dholbert]	VERIFIED	FIXED
1681183	Tab-modal print dialog's "Margins: None" option should allow users to print with page margins actually set to 0, regardless of unwriteable area	David Shin[:dshin]	RESOLVED	FIXED
851441	[css3-page] implement @page rule size attribute	Emily McDonough [:alaskanemily]	VERIFIED	FIXED
1663366	[Mac] Tab-modal print UI uses old dropdown menu appearance	Emilio Cobos Álvarez (:emilio)	VERIFIED	FIXED
1664413	Printing doesn't use current session cookies when in private mode	Emilio Cobos Álvarez (:emilio)	RESOLVED	FIXED
1676188	Cross origin iframe’s content is not displayed while using window.print() with fission enabled	Emilio Cobos Álvarez (:emilio)	RESOLVED	FIXED
1681941	Tooltips on sheet indicator buttons are not shown for the second hover action if the sheet indicator focus is not removed	Emma Malysz	VERIFIED	FIXED
1695645	"Sheets of paper" does not update when selecting "Print on both sides"	Haik Aftandilian [:haik]	VERIFIED	FIXED
1670871	Limit the number suggested inside the margins warning message to two decimals	Hanna Jones [:hjones]	VERIFIED	FIXED
454059	Creating PDF of web page: hyperlinks are lost.	Jonathan Kew [:jfkthame]	RESOLVED	FIXED
1140929	Have nsPrintJob not block on modal nested event loop for print settings	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1432651	Disentangle RemotePrintJobChild from nsPrintSettings, and kill off nsPrintSession	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1558588	Remove the code that opens the print progress dialog from the core printing code	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1657733	Audit tests that only run with print.tab_modal.enabled=false	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1657854	Only allow nsPrinterList objects to be created in the main process on all platforms.	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1668210	Prevent print settings being saved to unprefixed prefs on non-Android	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1669815	Remove now-useless "aInRange" outparam from nsPrintJob::PrintPage (and simplify nsPagePrintTimer::StartTimer() which consumes it?)	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1704178	Remove dead printing code that can't be executed in a tab-modal-printing world	Jonathan Watt [:jwatt]	RESOLVED	FIXED
1712104	Add a preference 'print.prefer_system_dialog' to allow printing directly via the system print dialog	Jonathan Watt [:jwatt]	VERIFIED	FIXED
1693069	When users choose "Customised" as their "Pages", automatically focus the range field	Matthew N. [:MattN]	RESOLVED	FIXED
1670027	Print selection is disabled inside the system modal if the print preview destination was set to “Save to PDF”	Matthew N. [:MattN]	VERIFIED	FIXED
1661663	Popular sites prevent the print preview Margins menu from working (users need a way to override @page margins)	Mark Striemer [:mstriemer]	RESOLVED	FIXED
844090	landscape pdfs are printed portrait with pdf.js		RESOLVED	FIXED
1521655	[meta] Support client-side printing in Google Docs and GSuite (Google Workspace)		RESOLVED	FIXED
1658749	Middle Click scroll is not working correctly in new Print Preview		RESOLVED	FIXED
1664489	Print preview telemetry for the legacy UI is broken	Jonathan Watt [:jwatt]	RESOLVED	WONTFIX
1659782	Move the print preview browser into print.html		RESOLVED	WONTFIX
1663436	No longer able to change header/footer strings, even via "Print using system dialog..." escape hatch		RESOLVED	WONTFIX
1663801	Only call saveSettingsToPrefs in the frontend code when the user actually prints		RESOLVED	WONTFIX
1668794	[Linux] Paper size naming shows an additional “Borderless” after every option		RESOLVED	WONTFIX
1660111	[meta] Add automated tests for new print dialog		RESOLVED	INACTIVE
1282045	print pdf with both orientations		RESOLVED	DUPLICATE
1660921	Clone scroll positions in print documents		RESOLVED	DUPLICATE
1663019	Print headers and footers & Print Backgrounds options are available for pdf documents		RESOLVED	DUPLICATE
1666825	Online bank statement page not printing correctly (at Smile Bank UK)		RESOLVED	DUPLICATE
1681214	Users' print-dialog margin choices aren't respected, if the content uses "@page { margin: ... }"		RESOLVED	DUPLICATE
1679535	Most of the new Print modal options are inaccessible on destination change if previously a print action was made using Foxit reader with the old modal		RESOLVED	DUPLICATE
1722063	MacOS - New Firefox Modal Print Dialogue Does Not Support Dynamic Airprint Printers		RESOLVED	DUPLICATE
1679392	GIF file fails to render sometimes while changing orientation or scale settings		RESOLVED	DUPLICATE
1558907	Open the print progress dialog from the frontend instead of the core printing code	Jonathan Watt [:jwatt]	RESOLVED	WORKSFORME
1660602	Profile janky rendering of print preview documents		RESOLVED	WORKSFORME
1661688	Crash in [@ objc_msgSend | +[NSString stringWithString:]] (from system dialog)		RESOLVED	WORKSFORME
1661706	Crash in [@ initializeAndMaybeRelock]		RESOLVED	WORKSFORME
1662135	New print preview UI very janky scrolling documents with multiple pages		RESOLVED	WORKSFORME
1663129	Crash in [@ mozalloc_abort | moz_xmalloc | NS_NewDOMEvent]		RESOLVED	WORKSFORME
1663556	Crash in [@ nsFrameLoader::MaybeCreateDocShell]		RESOLVED	WORKSFORME
1663629	Crash in [@ g_sequence_iter_get_sequence]		RESOLVED	WORKSFORME
1663911	Crash in [@ initializeNonMetaClass]		RESOLVED	WORKSFORME
1666677	Printing hidden frame causes tab crash in Firefox 80, and "An error occurred while printing" error in 81 & newer if you're using legacy print dialog		RESOLVED	WORKSFORME
1669191	Crash in [@ OOM | unknown | NS_ABORT_OOM | PLDHashTable::Add | gfxFontGroup::BuildFontList]		RESOLVED	WORKSFORME
1679405	[Windows] System dialog opens after trying to save the file with “Save to PDF”		RESOLVED	WORKSFORME
1678319	Print preview displays the webpage in Portrait mode for several Destinations while the Landscape option is active and opens the old System dialog on print/save		RESOLVED	WORKSFORME
1683558	Scaling pages in print preview is not applied on the actual print		RESOLVED	WORKSFORME
1674155	[macOS] Print preview displays wrong paper size if several steps are performed		RESOLVED	WORKSFORME
1670645	Printing the source page is extremely slow		RESOLVED	WORKSFORME
1674390	printing action changed and dont work well like last.		RESOLVED	INCOMPLETE
1689211	Print problems after auto-update to 85 on Windows 7 32-bit PC		RESOLVED	INCOMPLETE
1673248	PDF prints boxes where there is a space on macOS with Canon printer		RESOLVED	INCOMPLETE
1673147	Print Problem on EPSON LX-310 After Update 82.0		RESOLVED	INCOMPLETE
1661751	Firefox print dialog doesn't get past throbber & "Preparing Preview", starting in Firefox 80		RESOLVED	INCOMPLETE
1666914	Printer Paper Size Mismatch		RESOLVED	INCOMPLETE
1669365	BUG REPORT 81.0.1 (64 BIT) Firefox does not permit printing to any installed PDF app. Will not work with NuancePDF or native PDF in Windows.		RESOLVED	INCOMPLETE

187 Total; 125 Open (66.84%); 54 Resolved (28.88%); 8 Verified (4.28%);

Archive

See the archive page for the tables tracking work for older versions of Firefox that have now moved to Beta or released (these have been split out into a separate page to avoid slowing down loading of this page with more bugzilla queries than are necessary).