1769326 - text letter spacing is incorrect/inconsistent in this Google Doc

Status: RESOLVED DUPLICATE of bug 1919906

(Core :: Layout: Text and Fonts, defect)

Description

[Will]

Attachment: Firefox google doc spacing.png

Was just reading this Google Doc and noticed the text/letter spacing is inconsistent in Firefox. No issue in Chrome. https://docs.google.com/document/d/1BfIqMcJvmMFdk8e_KKeOEofz16610Mql6gmfeFhrsZk/preview

Not sure if it's specific to Google Docs or if it's just that font

Reminds me of these old Chromium bugs https://bugs.chromium.org/p/chromium/issues/detail?id=707713

https://bugs.chromium.org/p/chromium/issues/detail?id=645055

Comment 1

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

The Bugbug bot thinks this bug should belong to the 'Core::Layout: Text and Fonts' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Daniel Holbert [:dholbert]]

Thanks for the report! I can't reproduce on Linux, for what it's worth. So, there may potentially be some platform-specific aspect here. What OS are you using?

Comment 3

[Will]

Oops sorry about that. Windows 10 version 21H2

Comment 4

[Daniel Holbert [:dholbert]]

Thanks! I can reproduce on Windows 10 (in my case with these system display settings in case it matters: 1920x1080 resolution, 100% scaling)

This seems to be a regression, though it's a little while back:
Last good revision: 17e3c9ff2cad9711445a6c39df85925c8f347336 (2020-04-14)
First bad revision: afa247928245d02b1305a1850eb39f19b84a2f35 (2020-04-15)
Pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=17e3c9ff2cad9711445a6c39df85925c8f347336&tochange=afa247928245d02b1305a1850eb39f19b84a2f35

In that range, bug 1629787 stands out as a potential culprit, since it's the only commit to mention fonts / font-related stuff that I'm seeing.

Comment 5

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

Set release status flags based on info from the regressing bug 1629787

Comment 6

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

:jfkthame, since you are the author of the regressor, bug 1629787, could you take a look?
For more information, please visit auto_nag documentation.

Comment 7

[Daniel Holbert [:dholbert]]

(Also: bug 1770132 is ~similar in symptoms, but it goes back much further; e.g. I can reproduce that one in Nightly 2015-01-01, way further back than the range in comment 4 here.)

Comment 8

[Jonathan Kew [:jfkthame]]

(In reply to Daniel Holbert [:dholbert] from comment #4)

Thanks! I can reproduce on Windows 10 (in my case with these system display settings in case it matters: 1920x1080 resolution, 100% scaling)

This seems to be a regression, though it's a little while back:
Last good revision: 17e3c9ff2cad9711445a6c39df85925c8f347336 (2020-04-14)
First bad revision: afa247928245d02b1305a1850eb39f19b84a2f35 (2020-04-15)
Pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=17e3c9ff2cad9711445a6c39df85925c8f347336&tochange=afa247928245d02b1305a1850eb39f19b84a2f35

In that range, bug 1629787 stands out as a potential culprit, since it's the only commit to mention fonts / font-related stuff that I'm seeing.

I'd be a bit surprised if bug 1629787 was the actual cause here. Looking at the pushlog again, I wonder if it might be related to bug 1547286. Does setting gfx.canvas.remote to false make any difference?

Comment 9

[Daniel Holbert [:dholbert]]

You're right, it was the gfx.canvas.remote pref-flip. Thought that pref doesn't help in current Nightly -- we had a later change that regressed this even with that pref set to false.

This command...

mozregression.exe --pref "gfx.canvas.remote:false" --good 2020-04-16 -a https://docs.google.com/document/d/1BfIqMcJvmMFdk8e_KKeOEofz16610Mql6gmfeFhrsZk/preview

yields this more-recent regression pushlog for "bad" results here:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=21f27a8573cb738731685ad57bcf1ed8be456658&tochange=3ba451ee28d11b0456c319676dafa846a91523c7
which is "Bug 1730772: Do not use GDI classic rendering when rendering Canvas. r=jfkthame,jrmuizel" and does seem to be mostly font-related changes.

So: in Windows Nightlies, this initially regressed via the pref-flip in bug 1547286, and (if you manually flip that pref to false) it regressed later via bug 1730772.

Comment 10

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

Set release status flags based on info from the regressing bug 1547286

Comment 11

[Will]

Just saw this mentioned in this reddit thread https://bugzilla.mozilla.org/show_bug.cgi?id=1757081

https://www.reddit.com/r/firefox/comments/1g8mmdi/recently_switched_to_firefox_google_docssheets/

Comment 12

[Daniel Holbert [:dholbert]]

This bug here (the rendering shown in comment 0, with a gap between "v" and "A" in "Motivation") might have been fixed recently...

At least, I just rebooted into a rarely-used Windows environment and was able to immediately reproduce the bug in the Nightly version that I had there, which was version 131 (not sure what the exact datestamp); and after I let that Nightly auto-update and restart, I'm now unable to reproduce.

Comment 13

[Daniel Holbert [:dholbert]]

mozregression find-fix mode identified Bug 1919906 as the thing that fixed this for me. (The screenshots in that bug look a lot like the screenshot in comment 0, too, with awkward extra-space between some glyphs.)

So I'm not sure about bug 1757081, but for this bug here at least, I think we can consider it a duplicate of bug 1919906 (duping forward just because that's where the patch landed).

Will: if you're able to test Nightly and confirm, that'd be appreciated - thanks!