Windowless Mode Fix

As a reminder, Firefox 3.0.1 has a known crash problem with a wide variety of windowless mode SWFs. This has already been fixed in the Mozilla code tree and alpha builds are available for download. However, if you would prefer to wait until a new official Firefox release, you may wish to disable windowless mode in the Flash Player. You can do this (on any platform) by setting WindowlessDisable=true in the mms.cfg (which lives in /etc/adobe on Unix platforms).

31 Responses to Windowless Mode Fix

  1. Zbigniew L. says:

    You would better prepare windowless mode fix patch for current official firefox 3.0.1 source so we could patch it and compile it. It is a matter of finding it in nightly code and finetuning it for 3.0.1 source. [ Or you could get a current nightly build of Firefox. Or disable windowless mode in the Flash Player. Both solutions are less work for me. -Mike M. ]

  2. Max says:

    I’ve disabled windowless mode and the flash apps I was testing before now look fine. But still fullscreen mode takes Firefox 3.0.1 down. Perhaps this nifty backtrace can help getting to the bottom of this issue:*** glibc detected *** ../firefox-3.0/firefox-bin: free(): invalid pointer: 0xad8a32e0 ***======= Backtrace: =========/lib/tls/i686/cmov/[0xb691ad65]/lib/tls/i686/cmov/[0xb691e800]/usr/lib/[0xaa6b9925]…I won’t post the memory map here.Cheers!Max [ Is it repeatable? What if you disable hardware acceleration via the right-click menu? -Mike M. ]

  3. Robert says:

    mm.cfg and mms.cfg do not exist on my system. I have no /etc/adobe directory and my.adobe directory doesn’t contain anything but cache. I’ve done a global search on the root directory, no results returned. Am I out of luck? [ They won’t exist unless you manually create them. -Mike M. ]

  4. club foot says:

    Hi,I posted this earlier on another subject but never saw a response.I’m using Linux, and I have Flash 9 installed system-wide for my users who want to use Flash9. When I had installed Flash 10 betas locally in my account under ~/.mozilla/plugins, it would say the version of Flash 10 which was installed. Now, though, with Flash 10 rc, it shows the version 9 message, is this normal or has something changed in the rc installation? I did remove the .xpi and even went so far as to reboot, but it still shows up as version 9.

  5. default says:

    I know this is off-topic, but I have a request for us folks who are using the Flash player with nspluginwrapper… can you build a variant of the player with libcurl and libnss statically linked in? This would make life far easier for us.(License-wise, this shouldn’t be a problem with libcurl. libnss is LGPL-licensed though, and the LGPL implications for this case are quite complicated — I’m not sure if it is legal to link it into the player.)

  6. Mateus César Gröess says:

    Has Windowless Mode a special requirement? I’m asking because with Flash Player 10 RC (d569 according with about:plugins) and Firefox Shiretoko/3.1a1 Gecko/2008072306 rv:1.9.1a1, W-mode works on a PC with Ubuntu 8.04 and doesn’t work on a Slackware 12.0 one, both 32-bit distros. Flash plugin is loaded and runs, but W-mode is missing on the Slackware PC. Same problem with 2008-07-08-02-mozilla-central and some other builds. Could be some X11 parameter, video card, driver, GTK/GDK or other library version? The Ubuntu PC has a Riva TNT2 video card, using default driver and setup provided by Ubuntu, and the Slackware PC has Intel 865G, with driver xf86-video-intel-2.1.0. No mms.cfg or mm.cfg was installed. [ Are you viewing a windowless mode site? How do you know? -Mike M. ]

  7. Mateus César Gröess says:

    [ Are you viewing a windowless mode site? How do you know? -Mike M. ]Menus appear behind flash, e.g. on [ And you are certain it’s Flash 10 and not an old copy of Flash 9 that Mozilla is finding somewhere? -Mike M. ]

  8. Chad says:

    Ubuntu 8.04:Add “deb hardy main” to your repositories list, and upgrade ONLY xulrunner packages from this repository (lock everything else that claims to be upgradeable, since the firefox builds there don’t recognize the flash 10 player as a valid plugin).This gives you the ability to run Ubuntu’s official Firefox 3.0.1 with Flash 10, wmode, acceleration, and functional full-screen button – all without crashes or hangs.(Downside:’s default animation pegs the CPU and runs s-l-o-wly. But – it does run, and doesn’t crash.)

  9. Mateus César Gröess says:

    Just to add a little more info, with Flash 10 beta 2 (d525), windowless mode works on same Slackware PC, menus appear in front of flash animation on Asus website, but the animation image “jumps” when changing menus. This problem didn’t appear on the Ubuntu PC with Flash 10 RC installed. It just seems to disable windowless mode on Slackware PC for some reason.

  10. “Menus behind Flash …“OpenSuSE 10.3 64-bit with the latest Flash 10 player (Tools, addons, plugins) in 32bit FireFox 3.0.1 from the build service, shows menus in front of the Flash at that URL.

  11. Also, Flex Builder Linux can’t debug with the v10 player 🙁

  12. LuisManson says:

    Seems to work better than the last beta, i just have a huge performance lost with videos on google reader, choppy scrolling, video artifacts inside the flash area…slow video… i browsed youtube and some blogs with videos and everything is fine, so it has to be something within G reader…Screenshot: in the menu is behind the flash…32 bit Firefox 3.0.1 with Flash 10.0.0 d569, under Gentoo 64I can use my cam and TV tuner now, thanks…but where?

  13. singing mule says:

    Where may I re-download the beta 2, please? For some reason the RC doesn’t load for me, so if I may please download the beta 2, I’ll continue to use it until the final is out, thanks. Is there a specific directory where past versions may be obtained? I’m not finding the beta 2 download anywhere.

  14. Claude says:

    [quote][ Are you viewing a windowless mode site? How do you know? -Mike M. ]Menus appear behind flash, e.g. on And you are certain it’s Flash 10 and not an old copy of Flash 9 that Mozilla is finding somewhere? -Mike M. ][/quote]I confirm and I use Flash 10 lastest version. I check it by right clicking on a flash animation and about.Also I checked with the webpage and it says:LNX 10,0,0,569

  15. spispopd says:

    Actually, what would really rock would be a separate-process flash plugin WITHOUT nspluginwrapper in the first place. Not for 32/64 compat reasons, but to shield the browser session and all my open tabs from flash plugin crashes – and even when there’s a not-strictly-crashing but cpu-hungry flash thing running it’s annoying that the whole browser can become so unresponsive.There’s just no need for plugins to run in-process in this day and age of multi-GHz machines, particularly not on linux/x11 (where interprocess IPC is good and high-performance, and the window system explicitly supports different processes embedding child windows in eachother’s windows).The Sun Java plugin on linux recently implemented separate-process support, and very nice it is too:

  16. tester says:

    Tried the 10rc, and while it worked okay for most things, a friend who watches Y&R online complained they couldn’t watch it so I took a look and saw some weird white boxes moving and disappearing over the flash as it started, and the video that followed was VERY choppy. I downgraded them to Flash 9 and it shows as it should, you should take a look at this for yourself and draw a comparison, something really strange is going on, if this is a release candidate this should be addressed, see for yourself:'s the only problem I’ve noticed thus far, though I haven’t tested much beyond YouTube,, and a few other sites.

  17. tester says:

    Oh, and I have noticed crashes of the browser as usual with FF3 and 10rc, just like with version 9.

  18. oyvind says:

    It helped with a lot of crashes to disable windowless mode .. Hope another Firefox3 bugfix release isn’t too far away.Aside from that, I haven’t noticed too many problems with this RC. There are the occasional freeze-on-leaving a page incidents (this has plagued the Flash+Firefox+Linux combo for a long time, now), but my impression is that it doesn’t happen as often as with Flash9, so that’s an improvement. Thanks for your work on the Linux Flash player.

  19. neqael says:

    As for the libcurl problem, have you guys tried ? It’s really handy for downloading 32-bit libs.

  20. klaus says:

    Some videos on YouTube cannot be watched in HQ anymore with the RC. I know someone reported this earlier, I just wanted to confirm it.And no, the HQ files weren’t removed. They work fine when I go back to the beta. [ Acknowledged; unfortunate bug in the RC. We are fixing that for the final. -Mike M. ]

  21. sim c0rdz says:

    “And no, the HQ files weren’t removed. They work fine when I go back to the beta.”Where do I re-download the 2nd beta, please? I asked this before and received no answer, thanks. [ That’s because I have no answer. Beta 2 has passed into the great void. -Mike M. ]

  22. gothmog says:

    Hi,I’m wondering if it’s possible to download somewhere the beta 1.Thanks.

  23. finger foods says:

    Can someone please explain what the deal is on Linux with the .macromedia folder and subfolder?Here’s what I’ve found: Eventually, whether it’s version 9 (or 10 beta/rc) the browser will suddenly start crashing randomly when watching YouTube videos. After awhile this will be constant, and I’ll go and delete the files and subfolders in .macromedia in the user’s home directory after closing Firefox3, and restart FF3 and suddenly the crashes stop, for awhile. When they begin again I delete the contents of .macromedia and it’s stable for awhile. Sometimes this doesn’t resolve crashes but most of the time it does, usually only for a few hours.So what effect is this having by deleting the .macromedia folder contents, and is there any way you could implement some type of button to clear the .macromedia folder quickly and easily so I don’t have to go into .macromedia and do it myself at the command line every time? I know you can remove content from within the Flash Player Control Panel type of thing, I’ve done that but it still leaves behind stuff in .macromedia, which is why I end up manually deleting those files.

  24. I appreciate your support for Linux but the flash player is crap.I keep trying with different versions and I tried this fix, and it keeps crashing for me.For example with this site: can’t you have a decent issue tracking system? [ Probably because such a system would be inundated with detail-deficient reports, such as this one. -Mike M. ]

  25. What do you need? Backtraces?I have sent dozens to:

  26. Felipe Contreras says:

    Here, I got it manually:#0 0x0074696e in ?? ()#1 0xaf61a6eb in ?? () from /home/felipec/.mozilla/plugins/ 0xaf606bf9 in ?? () from /home/felipec/.mozilla/plugins/ 0xaf2c15c4 in ?? () from /home/felipec/.mozilla/plugins/ 0xaf2c20d8 in ?? () from /home/felipec/.mozilla/plugins/ 0xaf1ef064 in ?? () from /home/felipec/.mozilla/plugins/ 0xaf1f248c in Private_DestroyStream () from /home/felipec/.mozilla/plugins/ 0xb7b89ab3 in ?? () from /opt/firefox/ 0xaab9e058 in ?? ()#9 0xaaba9c00 in ?? ()#10 0x00000000 in ?? ()Who releases beta software without debugging symbols anyway?

  27. Anon says:

    Thanks for listing the workaround – this was the exact problem I was seeing on a myspace page. Is there any way to tell that flash in question is Windowless when it is crashing?

  28. kolja ginzer says:

    finger foods, you could just sym link .macromedia to a folder mounted as tmpfs. This way all the data in .macromedia will be lost with each boot. Ubuntu has a tmpfs by default at /dev/shm/ (probably other distros do as well).I’ve got /tmp/ mounted as tmpfs in my fstab and I linked .macromedia to /tmp/ with “ln -s /tmp/ ~/.macromedia” but you could just use /dev/shm/.I do this with loads of temp files to compensate for terrible ssd write speeds because I’ve got ram to kill. I’ve noticed no issues.

  29. Laurens Leemans says:

    Does this problem have anything to do with the fact that the standalone player won’t function properly in fullscreen mode without a window manager?I use flash a lot for digital signage and found that starting Flash 10 (and Flash 9.0.115 for that matter) directly from .xinitrc results in Flash just drawing the top-left 150×150 pixels of the screen(that’s an estimation), when Gnome is installed however, the player will do fullscreen properly. (Which is just useless overhead in my case)

  30. Chuck Crisler says:

    I am working on a Linux app that implements the NS plugin API and am testing with Flash 10. I need to use the ‘windowless’ mode, but Flash seems to stubbornly refuse. I have created a pixmap and put the XID into the NP_WINDOW structure passed in through SetWindow(), but that causes Flash to crash. This happens before the SWF data stream is opened to the plugin. I am specifying the NPNVGtk2 toolkit, XEMBED, Window type == drawable, mode as both NP_FULL or NP_EMBED. After calling NPP_new in Flash, a call to GetValue in Flash for the WindowBool variable returns ‘TRUE’, suggesting that Flash ONLY wants windowed mode. However, after reading on this blog I am hopeful that Flash really does support windowless mode on Linux. Can you make any suggestions (please)? BTW – I saw references to the nspluginwrapper project (a very helpful example), but that seems to ONLY support windowed mode. Is that correct? TIA, Chuck