515296 - open a popup window cant set "transparent" background color

Status: RESOLVED DUPLICATE of bug 428686

(Core :: General, defect)

Description

[mike8625]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.1.2) Gecko/20090729 

I open a window with popup style: 
openDialog("xxx.xul","","chrome,popup"); 
in the "xxx.xul" I set its window tag : "style='background-color: transparent '", but it shows white background color in the window.  
if I remove the "popup" style, the window can set transparent; 
And in gecko 1.90 it can set transparent in popup window .

Reproducible: Always

Steps to Reproduce:
1.openDialog("xxx.xul","","chrome,popup"); 
2.the "xxx.xul" window(root) tag add: style="background-color: transparent"

Actual Results:  
window's background color is not transparent

Expected Results:  
window's background color is transparent