1740451 - Black line on left, top and bottom sides of the scrollbar in print preview page on maximized browser window with screen scale from 125% upwards

Status: NEW

(Toolkit :: Printing, defect)

Description

[Timea Zsoldos [:zstimi/tzsoldos], Desktop QA]

Attachment: maximized screen and 125% scale.png

Note

• Ubuntu, macOS not affected.

Affected versions

• Firefox 95.0b5
• Firefox 96.0a1

Affected platforms

• Windows 10 x64

Steps to reproduce

1. Launch Firefox. Set the screen resolution to 125%.
2. Go to any random page.
3. Access the print preview page with Ctrl+ P.
4. In the new semi-modal printing UI, click on More settings option to display the scrollbar.
5. Maximized the Firefox window.

Expected result

• The scrollbar appears properly.

Actual result

• The scrollbar shows up with extra black lines on the left, top and bottom sides.

Regression range

• I will come back with regression range ASAP.

Additional notes

• On the top side the line appear and disappear when you scroll the scrollbar and hover on it, or drag and drop the scrollbar, somethings like that.

Comment 3

[Timea Zsoldos [:zstimi/tzsoldos], Desktop QA]

Regression range

• First bad: 2020-08-20 build ID: 20200820212107
• Last good: 2020-08-19 build ID: 20200819212829
• Pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=b0888d07df690ed43df31a2b013d12464b183a30&tochange=e375b85cfba38ff5f49493d1d48b7561f7f2f8d7
• Potential regressor: 1660291

Comment 4

[Timea Zsoldos [:zstimi/tzsoldos], Desktop QA]

Attachment: scrollbar screen 125%.png

Reproduced the scrollbar issue when opening "List all tabs" dropdown, on Windows 10 x64 with 95.0b7 using 32 bits build, reproduced with maximized and restore down Firefox window. With 64 bits build partially reproduced, black lines present only on the top and bottom sides of the scrollbar.

Comment 5

[Yasmin S]

emilio is the regressor here correct ?

Comment 6

[Emilio Cobos Álvarez (:emilio)]

No, most likely bug 1653317 instead. But we should consider just using non-native scrollbars on chrome code as well which I suspect wouldn't have this snapping issue.