804844 - Setting scrollTop doesn't affect scrollbar.

Status: NEW

(Core :: Layout, defect)

Description

[valts]

User Agent: Opera/9.80 (Windows NT 6.1; WOW64; U; en) Presto/2.10.289 Version/12.02

Steps to reproduce:

This is demonstrated in the following JSFiddle: http://jsfiddle.net/F5tdB/ and described in the following StackOverflow question: http://stackoverflow.com/questions/13040897/firefox-scrollbar-resets-incorrectly In the SO question there's also a workaround by one of the community members.

To reproduce:

1. Get an element with overflow:auto and some vertically overflowing contents, then scroll it down a bit;
2. Hide the element (display: none);
3. Remove contents
4. Show the element (it's empty now)
5. Re-add the same contents (it's scrolled now, just as it was before)
6. Set scrollTop to 0 via Javascript.


Actual results:

The contents got scrolled to the top, as is proper, but the vertical scrollbar itself stayed in the old (scrolled down) position.


Expected results:

The vertical scrollbar should also have scrolled to the top.

Comment 1

[Alice0775 White]

Attachment: standalone html

Comment 2

[Alice0775 White]

Regression window
Good:
Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9a1) Gecko/20060407 Firefox/3.0a1
Bad:
Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9a1) Gecko/20060408 Firefox/3.0a1

Bonsailog:
http://bonsai.mozilla.org/cvsquery.cgi?treeid=default&module=all&branch=HEAD&branchtype=match&dir=&file=&filetype=match&who=&whotype=match&sortby=Date&hours=2&date=explicit&mindate=2006-04-07+00%3A00%3A00&maxdate=2006-04-08+03%3A00%3A00&cvsroot=%2Fcvsroot
Forum log:
http://forums.mozillazine.org/viewtopic.php?f=23&t=402283

Suspected:
Bug 331607 - scroll position can not be retained in overflowing RTL blocks

Comment 3

[valts]

Why is Bug 331607 mentioned, and the related forum thread? This has nothing to do with RTL blocks.

Comment 4

[Alice0775 White]

(In reply to valts from comment #3)
> Why is Bug 331607 mentioned, and the related forum thread? This has nothing
> to do with RTL blocks.
This problem is a regression due to landing patch of Bug 331607.