1802941 - window reports wrong scroll Y position (unable to scroll to 0)

Status: NEW

(Firefox for Android :: Toolbar, defect)

Description

[Kevin Brosnan [Ex-Mozilla]]

From github: https://github.com/mozilla-mobile/fenix/issues/25278.

Steps to reproduce

1. Open https://developer.mozilla.org/en-US/
2. Scroll around the page
3. Check window.scrollY value
4. Observe that it's not 0 even if visibly at the top of the page

Expected behaviour

window.scrollY should be 0

Actual behaviour

window.scrollY is 0.7333333492279053

Device name

Pixel 4 API 30

Android version

Android 11.0

Firefox release type

Firefox

Firefox version

100.2.0

Device logs

No response

Additional information

Noticed the issue on my latest personal phone Firefox mobile app version from App store on Redmi 8T and some further testing was completed with remote debugging on emulated app (device info).

Things I've tried so far:

• I've tested on Firefox Mobile on my device and on emulator scrolling/dragging completely to the top.
  Visually it looks at top (impossible to scroll further top with "finger" or the mouse wheel)
  
• On emulator I've also tried to scroll with mouse wheel and it never gets to 0. It's usually stuck at 0.7333333492279053.
• I went on ahead and tested on some other web pages and the problem is there also.
• Tested with the address bar on bottom and on top. Same issue.
• Tried programmatically moving scroll to 0, same.
  

┆Issue is synchronized with this Jira Task

Change performed by the Move to Bugzilla add-on.

Comment 1

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

The severity field is not set for this bug.
:cpeterson, could you have a look please?

For more information, please visit auto_nag documentation.