Java rendered always on top except for iframe and certain overflow values




9 years ago
a year ago


(Reporter: Jeffrey Bush, Unassigned)


Firefox Tracking Flags

(Not tracked)




9 years ago
User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv: Gecko/2009011913 Firefox/3.0.6 (.NET CLR 3.5.30729) FirePHP/0.2.1
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv: Gecko/2009011913 Firefox/3.0.6 (.NET CLR 3.5.30729)

Java renders on top of everything, no matter the z-index or being cropped by it's container. This is a common problem in ALL rendering engines, I know (this is so common I really thought a bug should have already been submitted and I am sorry if there is, but I tried searching for many things with no luck).

However, Gecko is the closest to solving this problem. Both Gecko and IE/Trident allow you to do the IFRAME hack (see This does not work on Mac however.

Gecko can properly handle display: none and visibility: hidden on the Applet unlike all WebKit and Opera/Presto.

Gecko can also display a DIV floating over an Applet if the DIV has one of the following styles:

overflow-x: hidden
overflow-y: hidden (not both x and y to hidden though)
overflow: scroll (also work for either -x or -y)
overflow: auto (also work for either -x or -y)

With any of these set, a rectangular "hole" is cut in the applet and lets the webpage behind the applet render instead (this can be seen if you have a semi-transparent DIV over the applet).

So whatever code gets the overflow examples working should be applied to anything with a higher z-index than the applet. Even with the semi-transparent problems, that would be great progress. This could be the first rendering engine to do applets better!

Reproducible: Always

Steps to Reproduce:

1. Add an applet to a page (I used OBJECT tag, I believe it works with APPLET as well)
2. Add a DIV to the page with a higher z-index than the applet, absolute positioning, left/top values to get it over the applet, and a solid background color.
Actual Results:  
All you see is the applet

Expected Results:  
See the DIV over the applet
Reporter, can you confirm this is still a problem?

Comment 2

8 years ago
It is still a problem, in a way. I have made a test site:

Solid DIVs are rendered correctly. Semi-transparent DIVs are still a problem (and different than before). The applet is drawn on top of semi-transparent DIVs and overflow: values have no effect now.

Tested in the most recent release build:
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv: Gecko/20100401 Firefox/3.6.3 ( .NET CLR 3.5.30729)
I'm marking this bug as WONTFIX per bug #1269807.

For more information see -
Last Resolved: a year ago
Resolution: --- → WONTFIX
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