1535583 - [Youtube] Unsubscribed channel popup changes slightly its size on tab navigation

Status: NEW

(Core :: Layout: Text and Fonts, defect, P3)

Description

[Anca Soncutean, Desktop QA]

Attachment: screencast issue.gif

[Affected versions]:

• 66.0 (20190314174725)
• 67.0a1 (2019-03-14)

[Affected platforms]:

• Windows 10 x64
• Windows 7 x64
• Ubuntu 16 x32
• macOS 10.13

[Steps to reproduce]:

Precondition:

• Make sure to previously subscribed to a youtube channel

1. Go to https://www.youtube.com/ and login
2. Click the “Subscribed” button
3. Navigate with the Tab key inside the Unsubscribed popup

[Expected result]:

• No popup size modification is triggered by the Tab navigation action.

[Actual result]:

• The popup size slightly increases.

[Regression range]:

• This issue looks like an old regression, reproducible way back to Fx 47.0a1, but not on Fx 31.0a1. I will provide more information asap.

[Additional Notes]:

• Issue not reproducible with Chrome or Internet Explorer.

Comment 1

[Alice0775 White]

Disabled HWA fixes the issue on Nightly67.0a1 Windows10.
It seems difference of width of boldly(synthesized?) font rendering between browsers/text rendering engine.

Comment 2

[Anca Soncutean, Desktop QA]

I was able to restrain the regression range only to the following:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=9ed17db42e3e46f1c712e4dffd62d54e915e0fac&tochange=0b69d304f861d0038fb78f1d52b0f5d13ef7c6fe