1914517 - Emoji in mozPrintCallback (and Google Docs with Firefox's print dialog) get rasterized at low resolution

Status: NEW

(Core :: Printing: Output, defect, P3)

Description

[Daniel Holbert [:dholbert]]

Attachment: testcase 1 (mozPrintCallback with tada emoji glyph)

STR:

1. Load attached testcase.
2. Ctrl+P, save to PDF.
3. Ctrl+A to select all text in the PDF.
4. Zoom in on the tiniest emoji glyph (Ctrl+) and see if it scales crisply.

ACTUAL RESULTS:
The emoji glyphs are not selectable.
The small "tada" emoji glyph looks extremely fuzzy when zoomed.

EXPECTED RESULTS:
The glyph should be selectable and should zoom crisply (or at least more-crisply).

This reproduces with Google Docs as well, if you've been added to the new Google Docs native print flow (bug 1521655). I'll post another comment with STR for that.

Comment 1

[Daniel Holbert [:dholbert]]

Attachment: print-to-PDF result from testcase 1

Comment 2

[Daniel Holbert [:dholbert]]

STR with Google Docs:

1. Be opted in to the Google Docs native print flow (there's no user-exposed way to do that, but you can tell whether or not you're opted in based on whether Ctrl+P gets you a print dialog on a google doc vs. opens a new tab with a PDF)
2. Load this Google Doc:
   https://docs.google.com/document/d/1vG3j0h3EndY8rNvimthZyFf-R88tN--Z6Ji6gHEmRhk/edit?usp=sharing
3. Print (with e.g. Ctrl+P) and choose Firefox's "Save to PDF" print target.
4. Open the resulting PDF (e.g. in Firefox itself, or in Chrome), and try select-all and zooming in on the smaller emoji glyph.

ACTUAL RESULTS:
The emoji glyphs are not selectable.
The small "tada" emoji glyph looks extremely fuzzy when zoomed.

EXPECTED RESULTS:
The glyph should be selectable and should zoom crisply (or at least more-crisply).

Comment 3

[Daniel Holbert [:dholbert]]

Attachment: print-to-PDF result from Google Docs example in Firefox with browser print dialog

Comment 4

[Daniel Holbert [:dholbert]]

Attachment: print-to-PDF result from Google Docs example in Firefox with server-side PDF generation (the old flow)

Comment 5

[Daniel Holbert [:dholbert]]

Attachment: print-to-PDF result from Google Docs example in Chrome with browser print dialog

Comment 6

[Daniel Holbert [:dholbert]]

Attachment: screencast comparing those last 3 PDFs at 10x (1000%) zoom factor

Here's those last 3 PDFs in order (left to right), viewed in Firefox at 10x zoom factor (the most that PDF.js allows me to zoom in).

The leftmost one -- the one generated in Firefox with the native print flow -- is substantially fuzzier than the other two (because it's just a rasterized image, I suspect).

Comment 7

[Daniel Holbert [:dholbert]]

Both Firefox-with-server-side-PDF-generation and Chrome (with its built-in print dialog) give EXPECTED RESULTS here, FWIW (as can be seen from the attached PDFs).

So: right now this represents a bit of a regression, resulting from our gsuite native-print-dialog work.

jfkthame, could you take a look at this if you've got some cycles? How much trouble is it to get "real" copypastable (and nicely scaling) emoji glyphs in our PDF output here?

Comment 8

[Daniel Holbert [:dholbert]]

Also, I should mention I'm testing with Firefox 131.0a1 (2024-08-21) (64-bit) on Ubuntu 22.04 -- I don't imagine this is OS-specific, but it's worth testing on other platforms when possible, which I haven't done yet.

Comment 9

[Emilio Cobos Álvarez [:emilio]]

Daniel, could you assess severity? Feels like S3-ish to me but worth double-checking :)

Comment 10

[Daniel Holbert [:dholbert]]

sorry, missed the bugmail - I agree, S3 feels right.