555720 - Div with overflow styled with shadow problematic scrolling

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[Brett]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; en-GB; rv:1.9.2.2) Gecko/20100316 Firefox/3.6.2
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-GB; rv:1.9.2.2) Gecko/20100316 Firefox/3.6.2

Situation:

created a div with the following style

-moz-border-radius:6px;-moz-box-shadow:5px 5px 15px #bbb, -5px 0 15px #bbb;-webkit-border-radius:6px;-webkit-box-shadow:5px 5px 15px #bbb, -5px 0 15px #bbb;  border:2px #0DBCDF solid;display:block; position:relative; background-color:#FFF;padding:5px;z-index:100;height:509px;	top:0px;left:0px;width:720px;overflow:auto;

add content that overflowed and tried to use the scroll bar to view the content

Result:

Scrolling bar is extremely slow to scroll up or down.  page up or page down scrolls at a few lines of content instead of a page amount of lines.  Page down to the bottom of the content took 75 "page down key" presses to view the last line of the 100 lines of content.

Tested:

removed the following from styling

-moz-border-radius:6px;-moz-box-shadow:5px 5px 15px #bbb, -5px 0 15px #bbb;-webkit-border-radius:6px;-webkit-box-shadow:5px 5px 15px #bbb, -5px 0 15px #bbb;

Result:

page down worked fine, 2 page downs to see the last line of content, scrolling normal speed, no lag or latency.

Reproducible: Always

Steps to Reproduce:
1.Create a normal HTML doc with a <div> with style

-moz-border-radius:6px;-moz-box-shadow:5px 5px 15px #bbb, -5px 0 15px #bbb;-webkit-border-radius:6px;-webkit-box-shadow:5px 5px 15px #bbb, -5px 0 15px #bbb;  border:2px #0DBCDF solid;display:block; position:relative; background-color:#FFF;padding:5px;z-index:100;height:509px;	top:0px;left:0px;width:720px;overflow:auto;

2. Create 100 lines of content i.e. <br/>test 100 times inside the <div>

3. Load the page in Mozilla and try scroll up or down on the scroll bar and it lags and is extremly slow

4. page up or page down for the <div> in focus and content isnt viewed as expected
Actual Results:  
Mozilla froze for a while after the test and started to consume a large amount of ram, continued to do so until I closed it.  Restarted Mozilla - restarted a new session and tried the test again.  Exact same results.  

Expected Results:  
Fast scrolling as per the div without the shadow and moz radius styling

Comment 1

[zug_treno]

Related to/duplicate of bug 438911 or Core bug 469589?

Comment 2

[Tyler Downer [He/Him]]

Reporter, are you still seeing this issue with Firefox 3.6.13 or later in safe mode? If not, please close. These links can help you in your testing.
http://support.mozilla.com/kb/Safe+Mode
http://support.mozilla.com/kb/Managing+profiles

You can also try to reproduce in Firefox 4 Beta 8 or later, there are many improvements in the new version, http://www.mozilla.com/en-US/firefox/all-beta.html

Comment 3

[Tyler Downer [He/Him]]

No reply, INCOMPLETE. Please retest with Firefox 3.6.13 or later and a new profile (http://support.mozilla.com/kb/Managing+profiles). If you continue to see this issue with the newest firefox and a new profile, then please comment on this bug.