1448423 - browser.startup.blankWindow causes window to be visibly resized on startup with privacy.resistFingerprinting (RoundWindowSize)

Status: VERIFIED FIXED

(Core :: Privacy: Anti-Tracking, defect, P3)

Description

[Vishinko]

User Agent: Mozilla/5.0 (Windows NT 6.1; rv:52.0) Gecko/20100101 Firefox/52.0
Build ID: 20100101

Steps to reproduce:

Run latest Nightly, enable privacy.resistFingerprinting, and close then open the browser.


Actual results:

The window gets maximized then minimized again.


Expected results:

The window shouldn't be maximized in the first place.

Comment 1

[Marion Daly [:mdaly]]

Hey Tom, Is this shipping in 61?

Comment 2

[Tom Ritter [:tjr]]

(In reply to Marion Daly [:mdaly] from comment #1)
> Hey Tom, Is this shipping in 61?

Resist Fingerprinting is a non-default preference; it is present in 61, but it is not on by default.

Comment 3

[Marion Daly [:mdaly]]

Making it a fix-optional for 61 then.

Comment 4

[Tom Ritter [:tjr]]

I might have reproduced this?  Ubuntu 17.10 x64

Enable RFP
Maximize the window
Close Firefox
Open Firefox
It opens maximized, then visibly resizes to rounded dimension

Also:
Enable RFP
Resize Window to be non-maximized but slightly larger than rounded dimensions
Close Firefox
Open Firefox
It opens at the previous size then visibly resizes to rounded dimensions


If I disable browser.startup.blankWindow then the window will _start_ with the same resized dimensions as before, instead of visibly resizing in front of me.

So something in browser.startup.blankWindow definitely is affecting this.  But the resulting resized behavior I think is what we intended? Want to double check with Arthur.

Comment 5

[Arthur Edelstein [:arthur]]

I think ideally, on startup, the window should open directly to the RFP dimensions, without any visible resizing.

Comment 6

[Florian Quèze [:florian]]

(In reply to Tom Ritter [:tjr] from comment #4)

> So something in browser.startup.blankWindow definitely is affecting this.

Yes, see https://searchfox.org/mozilla-central/rev/7e663b9fa578d425684ce2560e5fa2464f504b34/browser/components/nsBrowserGlue.js#52-65

(In reply to Arthur Edelstein (Tor Browser dev) [:arthuredelstein] from comment #5)
> I think ideally, on startup, the window should open directly to the RFP
> dimensions, without any visible resizing.

Right, so I think the question is why are the sizemode, width and height set by RFP not persisted in XULStore.

Comment 7

[Fatih Kilic [:fkilic] (OOO -> Aug 12)]

I think this bug was resolved with Bug 1897590. Are you still able to reproduce this bug?

Comment 8

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

Redirect a needinfo that is pending on an inactive user to the triage owner.
:sclements, since the bug has recent activity, could you have a look please?

For more information, please visit BugBot documentation.

Comment 9

[Sarah Clements [:sclements]]

Since the reporter is inactive and this bug was filed 7 years ago, I'm going to close this out as fixed per comment 7. Please reopen if it isn't.

Comment 10

[Kestrel]

I can still reproduce Comment 4 STR on Windows and Linux with browser.startup.blankWindow = true. On Linux this setting is Nightly-only.

FPP can be used as an alternative to RFP which allows disabling the window rounding behavior:

privacy.resistFingerprinting = false
privacy.fingerprintingProtection = true
privacy.fingerprintingProtection.overrides = +AllTargets,-RoundWindowSize

Comment 11

[Fatih Kilic [:fkilic] (OOO -> Aug 12)]

Attachment: Bug 1448423: Skip earlyBlankFirstPaint if RoundWindowSize RFP target is enabled. r?tjr

Comment 12

[Fatih Kilic [:fkilic] (OOO -> Aug 12)]

Attachment: Bug 1448423: Allow passing IsPBM to ChromeUtils::ShouldResistFingerprinting. r?tjr

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/ac0d0fe55391
Allow passing IsPBM to ChromeUtils::ShouldResistFingerprinting. r=tjr
https://hg.mozilla.org/integration/autoland/rev/93e49e407bc1
Skip earlyBlankFirstPaint if RoundWindowSize RFP target is enabled. r=tjr,Gijs

Comment 14

[amarc]

Backed out for causing bc fails @ browser_startup.js

• Backout link
• Push with failures
• Failure Log
• Failure line:

TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_startup.js | should have no unexpected modules loaded before profile selection - Got 1, expected +0

Comment 15

[Fatih Kilic [:fkilic] (OOO -> Aug 12)]

Hmm sorry about that. Didn't know we couldn't use modules before profile selection

Comment 16

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/7880471154e3
Allow passing IsPBM to ChromeUtils::ShouldResistFingerprinting. r=tjr
https://hg.mozilla.org/integration/autoland/rev/8582362518f1
Skip earlyBlankFirstPaint if RoundWindowSize RFP target is enabled. r=tjr,Gijs

Comment 17

[Cristina Horotan [:chorotan]]

https://hg.mozilla.org/mozilla-central/rev/7880471154e3
https://hg.mozilla.org/mozilla-central/rev/8582362518f1

Comment 18

[Ciprian Georgiu, Desktop QA]

I have reproduced this issue using an affected Nightly build (2025-01-01), following the STR from comment 1.

The issue is verified as fixed on Beta 136.0b2, with Win 11, Ubuntu 24 and macOS 14.