376900 - IFRAMEs in S5 slide shows fail to load

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[Will Martin]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.1) Gecko/20061204 Firefox/2.0.0.1
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.1) Gecko/20061204 Firefox/2.0.0.1

I wasn't sure which component to file this under, so I selected General.  In fact, I'm not even sure whether this is a bug or a feature.  All I know is it's screwing up my presentations.

I'm using an IFRAME element in an S5 slide show.  You've probably heard of S5, but just to recap, it's a nifty JavaScript that lets you treat an HTML document as a slide show (like a PowerPoint presentation).[1]  I love using IFRAME with this, because it lets me put a live web page right in one of my slides.  When I reach the slide, I can demonstrate exactly what I'm talking about, click links, whatever, and then continue.

Unfortunately, as of FireFox 2.0.0.1 and higher, this technique no longer works.  The symptoms are really weird.  When I get to the slide containing the IFRAME, the page has not loaded.  The screen space is reserved, but it just shows the underlying background.  I KNOW that the source code for the linked page was downloaded and rendered: I've got the HTML Validator extension,[2] and it checks the source code for the IFRAME as well as the slide show.

The IFRAME works in IE 6 and in Safari.  I downloaded multiple versions of Firefox, and did some testing using the URL I gave above):

Firefox 1.5.0.11: IFRAME works
Firefox 2.0.0.0: IFRAME works
Firefox 2.0.0.1: IFRAME does not work
Firefox 2.0.0.2: IFRAME does not work
Firefox 2.0.0.3: IFRAME does not work

It took ages to do all that testing, since I completely uninstalled Firefox and wiped my profile for each version (thank goodness for sandbox machines).

If I disable JavaScript, then the IFRAME works perfectly in all versions.  Unfortunately, disabling JavaScript also destroys its usefulness, because in the absence of JavaScript the file is not a slide show.  It's just a rather boring-looking HTML page.

Furthermore, there's some really weird behavior regarding which slide the IFRAME is in.  Sometimes, if it's in a slide which is even partially visible on the screen during the initial loading sequence, before the JavaScript runs, then the IFRAME loads fine, and its contents remain visible.  Other times, the IFRAME will load, but then when I get to the slide with the IFRAME, its contents are gone.  This sometimes-there-sometimes-not behavior is really bizarre.  I haven't been able to pin down what's causing it exactly; I can tell you that the times it worked properly (when the IFRAME was initially visible) all occurred in 2.0.0.3.  You can see a test case with an IFRAME that's close to the top here:

http://instructors.cwrl.utexas.edu/~martin/Audit/show/test.html

As I said at the beginning, I'm not sure whether this is a bug or a feature.

It might be a bug because it's really weird that the IFRAME would download the source code but not render it, and because it happens so erratically.

It might be a feature because phishers sometimes try to use hidden IFRAMEs in evil ways.  Because the S5 scripts depend on altering the visibility of the slide elements, the IFRAMEs aren't always visible.  So Mozilla may be suppressing the output of the IFRAME on the theory that it might have been part of a phishing scheme.

Could someone please tell me whether this is a bug or a feature?  If it's a bug, it's really weird, but also obscure.  If it's a feature, then it's having some unintended consequences.  And either way, I'd like a work-around if anybody can think of one.  I have a presentation coming up on Wednesday, and I need my IFRAMEs.  Links won't do, because the whole point of the presentation is to demonstrate the use of IFRAME in a slide show!

I could use Internet Exploder, but I think I'd rather slit my wrists.  I could use Safari, and that's actually an option since the classroom where I'm presenting is equipped with both Mac and PC.  Or, I could sneak in early, remove Firefox 2, replace it with Firefox 1.5, and then swap Firefox 2 back in again after my presentation is over.  Assuming that the user account on the presentation PC has appropriate permissions to install/remove software.  Egad.






[1] You can read more about S5 here: http://meyerweb.com/eric/tools/s5/
[2] http://users.skynet.be/mgueury/mozilla/

Reproducible: Always

Steps to Reproduce:
1. Visit the supplied URL in Firefox 2.0.0.1 or higher
2. Observe that the IFRAME is just a blank box
3. Run in circles, scream and shout

Comment 1

[Adam Guthrie]

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3

This works for me in 2.0.0.3, so I'm not quite sure what's going on here. Can you reproduce this in a clean profile? http://kb.mozillazine.org/Profile_folder

Comment 2

[Ng Ming Hong]

WFM: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3

Comment 3

[Will Martin]

Okay.  Uninstalled Firefox, wiped my profile, installed a fresh copy:

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3

And it's still behaving erratically.  There are two IFRAMEs in the S5 slide show at this URL:

http://instructors.cwrl.utexas.edu/~martin/Audit/show/test.html

The one in slide 2 is working fine.  But the one in slide 5 is not.  It should be showing scholar.google.com in slide 5, but I get a blank box.  I'll attach a screenshot.

Comment 4

[Will Martin]

Attachment: Screenshot showing problem

I activated the context menu for the screenshot - note the lack of a "Frame" submenu.

Comment 5

[Samuel Sidler (old account; do not CC)]

I can occasionally reproduce this using Firefox 2.0.0.3 on Windows XP. I can never reproduce it on Mac OS X. And I can confirm comment 5; the iframe in slide 2 shows, but not the one in slide 5. If you turn off the stylesheet, they both display fine.

I'm not really sure what to make of this...

Comment 6

[aravindm]

Unable to test the url : http://instructors.cwrl.utexas.edu/~martin/Audit/show/test.html

Page not found
The requested page could not be found.

Comment 7

[Tyler Downer [He/Him]]

This bug was reported on Firefox 2.x or older, which is no longer supported and will not be receiving any more updates. I strongly suggest that you update to Firefox 3.6.3 or later, update your plugins (flash, adobe, etc.), and retest in a new profile. If you still see the issue with the updated Firefox, please post here. Otherwise, please close as RESOLVED > WORKSFORME
http://www.mozilla.com
http://support.mozilla.com/kb/Managing+profiles
http://support.mozilla.com/kb/Safe+mode

Comment 8

[Tyler Downer [He/Him]]

No reply, INCOMPLETE. Please retest with Firefox 3.6.x 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.