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Flash videos won't play full screen

If you are able to view Flash videos but you are unable to view them if you try to make them full screen, then you may have a problem with the Flash player and your video drivers. This article describes how to work around this problem.

Preload the library

On Linux, this problem can often be resolved changing the command used to launch Firefox so that a graphics library is loaded along with Firefox:

  1. Ubuntu (and other GNOME-based distributions): Click on the Preferences menu and select Main menu. The Main Menu window appears.
  2. Click on the program group called Internet.
  3. Select Firefox Web Browser and click on the Properties button. The Launcher properties window appears.
  4. Insert the string env LD_PRELOAD=/usr/lib/ before the text specified in the Command field:

  5. Click on Close to dismiss the Launcher properties window.
  6. Click on Close to exit the Main menu window.

If the problem is not solved, go to the next section.

Reset Zoom

Press and hold commandCtrl while pressing 0 to reset the Firefox zoom.

If the problem is not solved, go to the next section.

Disable Flash hardware acceleration

Note: When Flash videos are in full screen, the use of hardware acceleration depends on a Flash setting and not the Firefox hardware acceleration setting.

First make sure you are using the latest version of Flash (to check your version visit this Adobe test page) and then do the following:

  1. Go to this Adobe Flash Player Help page.
  2. Right-clickHold down the Ctrl key while you click on the Flash Player logo on that page, then click on Settings in the context menu. The Adobe Flash Player Settings screen will open.
  3. Click on the icon at the bottom-left of the Adobe Flash Player Settings window to open the Display panel.
  4. Remove the check mark from Enable hardware acceleration.

  5. Click Close to close the Adobe Flash Player Settings Window.
  6. Restart Firefox.

If this workaround allows you to view full screen videos, you should try to update your graphics drivers.

If the problem is not solved, go to the next section.

Unredirect full screen windows in Compiz

Compiz OpenGL compositing manager is known to interfere with displaying Flash in full screen.

  1. Go to Compiz Config manager > General Options
  2. Check mark Unredirect Full Screen Windows.

Based on information from Web Upd8

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Revision #:
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I followed all the instructions on the page to disable hardware acceleration, and upgraded to the most recent version of Flash for my Firefox 4 on my Mac OS X, but the full-screen video still does not work.

I exited & reopened but nothing :( Help!

(It's mainly on XTube, but on YouTube it works fine.)


I use a MacBook Pro with the latest everything. And I had the same problem. I thought it was because I had just upgraded Firefox to level 4. I discovered I was in the zoomed - in mode and returned it to standard size. Choose the 'View' drop down menu. Then choose 'Zoom' and 'Zoom Out'. Then try the full screen option during your video playback.

fxer2011 added a Reset Zoom section specific to Windows.

Based on fxer2011's edit, I simplified the introduction, removed the Flash links, added a TOC, removed the {for win} in the Reset Zoom section, simplified the Reset Zoom section, renamed the HW accel. & Compiz section heading, added a note to clarify when Firefox & Flash HW accel. are used, added a link to Upgrade your graphics drivers to use hardware acceleration and WebGL, made the source specific to Linux. It needs review.

Only tweaks were:

  • I removed the step number from the single step instruction
  • I replaced "HW" with "hardware"

I made an edit to remove mentioning YouTube. (While I was at it, I replaced the content about disabling hardware acceleration in Flash settingswith the recently approved Template:DisableHWAflash).

This article is currently titled, "Flash video won't play full screen on YouTube, Facebook and other websites". YouTube won't be using Flash as of Firefox 36 so we have to rename the article. Ref:

I would suggest renaming this article to: "Cannot view full screen Flash videos" (that's how the issue is described in Flash Plugin - Keep it up to date and troubleshoot problems).

Any other suggestions?

Copied from new posts today in /forums/contributors/711053

philipp said

i think mse support on release is going to be postponed because it might be responsible for the high current crash rate in firefox beta:

... and I wrote,

Bug 1129039 - Disable MSE for Firefox 36 was fixed so I took that to mean that Mozilla worked it out with Google to allow fallback to Flash for YouTube videos in Firefox 36. Look through bug 1125621 for more info.

I would still suggest renaming this article to: "Cannot view full screen Flash videos" (that's how the issue is described in Flash Plugin - Keep it up to date and troubleshoot problems) and not mention specific websites. HTML5 will likely replace Flash in YouTube and other sites, if not in Firefox 36 then in a future version.

I agree with the new title you're proposing, Alice.

I tried changing the article title to Cannot view full screen Flash videos and got this error:

A document with this title already exists in this locale.

It seems that this article was previously named "Cannot view full screen Flash videos" and was later renamed, so that title now redirects - See

So, unless you want to delete the redirect, what about renaming the article to this? Cannot view full screen Flash video (remove the "s")

or maybe this? (Actually, I like this one better!) Flash videos won't play full screen

I went ahead and renamed this article to: Flash videos won't play full screen

(I didn't want Joni to waste any more time on this and didn't think she'd mind)