Opened 16 months ago

Last modified 13 months ago

#25247 needs_revision defect

mochitest failures for #23104 patch

Reported by: arthuredelstein Owned by: tbb-team
Priority: Medium Milestone:
Component: Applications/Tor Browser Version:
Severity: Normal Keywords: tbb-fingerprinting, tbb-regression, TorBrowserTeam201806
Cc: igt0 Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description

I ran the mochitests for the #23104 patch on our tor-browser-52.6.0esr-8.0-2 branch on Debian GNU/Linux 9.1 and I ran into the following failures:

Passed: 3
Failed: 3
Todo: 0
failed | Line Height validation - got 20.4, expected 19.8
failed | Line Height validation - got 20.4, expected 19.8
failed | Line Height validation - got 20.4, expected 19.8
passed | Line Height validation
passed | Line Height validation
passed | Line Height validation

Child Tickets

Attachments (1)

0001-bug-25247-Update-bug23104-test-to-be-DPI-independent.patch (2.0 KB) - added by igt0 16 months ago.

Download all attachments as: .zip

Change History (11)

comment:1 in reply to:  description Changed 16 months ago by igt0

I was not able to reproduce, however, I think the issue is related to pixel density + font rendering. The test sets the font-size to 16.5px, however in the failures you posted, the css font size was rounded up to 17px by the browser.

That said, I tried a different approach:

https://trac.torproject.org/projects/tor/attachment/ticket/25247/0001-bug-25247-Update-bug23104-test-to-be-DPI-independent.patch

Could you give a try?

Replying to arthuredelstein:

I ran the mochitests for the #23104 patch on our tor-browser-52.6.0esr-8.0-2 branch on Debian GNU/Linux 9.1 and I ran into the following failures:

Passed: 3
Failed: 3
Todo: 0
failed | Line Height validation - got 20.4, expected 19.8
failed | Line Height validation - got 20.4, expected 19.8
failed | Line Height validation - got 20.4, expected 19.8
passed | Line Height validation
passed | Line Height validation
passed | Line Height validation

comment:2 Changed 16 months ago by igt0

Status: newneeds_review

comment:3 Changed 16 months ago by arthuredelstein

Status: needs_reviewneeds_revision

Thanks for your quick patch! Now I get:

Passed: 5
Failed: 1
Todo: 0
passed | Line Height validation
failed | Line Height validation - got 20.4, expected 20.7
passed | Line Height validation
passed | Line Height validation
passed | Line Height validation
passed | Line Height validation

Seems like the different rounding behavior on different Linux machines would be a fingerprinting vector as well.

comment:4 Changed 16 months ago by cypherpunks

Component: - Select a componentApplications/Tor Browser
Keywords: TorBrowserTeam201802 added

Arthur! Come back to the Tor Browser team :)

comment:5 Changed 16 months ago by gk

Owner: set to tbb-team
Status: needs_revisionassigned

comment:6 Changed 16 months ago by gk

Status: assignedneeds_revision

comment:7 Changed 16 months ago by gk

Keywords: TorBrowserTeam201803 added; TorBrowserTeam201802 removed

Adding to our March plate.

comment:8 Changed 14 months ago by gk

Keywords: TorBrowserTeam201804 added; TorBrowserTeam201803 removed

Moving our tickets to April.

comment:9 Changed 14 months ago by gk

Keywords: TorBrowserTeam201805 added; TorBrowserTeam201804 removed

Moving remaining tickets to May.

comment:10 Changed 13 months ago by gk

Keywords: TorBrowserTeam201806 added; TorBrowserTeam201805 removed

Moving our tickets to June 2018

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