1883717 - Incorrect pixel count of screenshots on macOS with component Screenshots enabled

Status: VERIFIED FIXED

(Firefox :: Screenshots, defect, P3)

Description

[Simona Badau, Desktop QA]

Attachment: Screenshot with the issue

Found in

• Nightly 125.0a1

Affected versions

• Nightly 125.0a1

Tested platforms

• Affected platforms: macOS 13, macOS 14
• Unaffected platforms: Ubuntu 22.04, Windows 10 x64

Steps to reproduce

1. Navigate to reddit.com
2. Take a screenshot of one of the photos
3. Observe the pixels counter.

Expected result

• The pixel count should match the resolution of the device.

Actual result

• The size of the screenshot is larger than expected. For example, on a MacBook device with a resolution of 1792 x 1120, the recorded size of the screenshot is 1,500x1,408 px. Please see the attached screenshot for more details.

Regression range

• This is not a regression, it's reproducible only when the component version of Screenshots is enabled.

Additional notes

• When using the extension version of Screenshots ('screenshots.browser.component.enabled' set to false in about:config) or the OS integrated tool, the size of the same picture is around 750 x 705 px.
• Issue reproducible on a MacBook Pro 16-inch, 2019.

Comment 1

[Niklas Baumgardner [:niklas]]

The reason this is happening is because macOS has a device pixel ratio of 2. This is reproducible on any device with a device pixel ratio that isn't 1.

Comment 2

[Niklas Baumgardner [:niklas]]

Attachment: Bug 1883717 - Correctly display screenshot size in overlay. r=sfoster

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f2cf1858cea8
Correctly display screenshot size in overlay. r=sfoster,firefox-desktop-core-reviewers

Comment 4

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/f2cf1858cea8

Comment 5

[BugBot [:suhaib / :marco]]

The patch landed in nightly and beta is affected.
:niklas, is this bug important enough to require an uplift?

• If yes, please nominate the patch for beta approval.
• If no, please set status-firefox125 to wontfix.

For more information, please visit BugBot documentation.

Comment 6

[Simona Badau, Desktop QA]

Verified as fixed using the latest Nightly 126.0a1 on macOS 13.2 and macOS 14.