Like many of you, I'm working with two monitors. I'm trying to watch an episode on Channel9's vid-cast, but every time I click back onto my other monitor, the video exits fullscreen-mode, and goes back to a tiny box on the page. Is it possible to keep a video in full screen, while working on the second monitor?


Flash is designed to not let you use full screen while it doesn't have focus. Probably to keep web pages from taking over your desktop.

I can't speak for silverlight, but flash will:

  • Always close fullscreen on ESC
  • Always mention the ESC key on fullscreen
  • Always close when it loses focus
  • Never initiate via a button press (only a mouse click)
  • Require a user to initialize (flash can't start fullscreen without a mouse click)

It is possible to change one of the DLL files flash uses with a hex editor to keep it open. The exact steps to change the DLL changes with every flash version. Here is a YouTube link, but for those who find watching a 30 second video to obtain a pragraph of text horrendously inefficient, here is a (paraphrased) transcript.

Find NPSWF32.dll (possibly at C:\Windows\System32\macromed\Flash\npswf32.dll
In version change 0x136340 from 74 to EB
In version 9 it's 0xC1487
In version it's 0x137349

This will probably break on every flash upgrade.

  • I know how to close flash...I'm asking how to keep it opened ;) – Sampson Aug 13 '09 at 19:12
  • It's designed to close when it loses focus. You can't keep it opened. – Grant Aug 13 '09 at 19:14
  • Grant, I know it's designed to do that. But SuperUsers deal with esoteric knowledge and hackery ;) I want to know how it's possible to achieve the opposite. – Sampson Aug 13 '09 at 19:14
  • Worked beautifully, I used address 0x00137C7E (74->EB) for version as posted in the YouTube comments. Version: adobe.com/software/flash/about – Christopher Galpin Feb 25 '10 at 9:00

With my multi-computer setup I am able to keep the windows full sized with Synergy but the full size screen must not be the one the Keyboard and Mouse is shared out from. Another option would be the VM as listed above. But you might have flicker problems with the video refresh.

I do with the 4 monitors across 3 computers.


This isn't quite full screen, but it's full width. I just modify the URL to use the youtube.com "embedded" option. You delete the "watch?" and replace "=" with "/".

For example:




Same video, just different interface. It's worked on every video for me so far.


There's a remedy now, at least for Flash:

If you have two or more monitors, then you have probably experienced this: When watching a fullscreen flash video on one screen you go to work on the other screen and flash immediately exits fullscreen mode.

FlashHacker is a tool which makes hacking and unhacking a flash install incredibly easy. It should work on most versions of flash.

enter image description here

  1. Close all browsers (enables flashhacker to edit flash)
  2. Run FlashHacker
  3. Click 'Hack My Flash!'
  4. Go back to browsing

As you know, you can't make the embedded Flash player do this. What you can do is use a video-specific downloader like the Firefox Plugin Flashgot to grab the file and play it locally in something that you can resize to almost full screen (perhaps the stand-alone/developer version of Flash Player).

Another kludgey option, if you have a lightweight VM on your machine, set to fullscreen on your second monitor and browse to Channel9 on that. Set to full screen and switch back to your host OS.


Flash Player 10.2+ allows you to watch flash videos in full screen on one monitor while working on the second.

With multiple display full screen support in Flash Player 10.2, you can now easily watch your favorite videos in true full screen on one display while you multitask on another


I just discovered that a while back "D.I.Z." released the patch for flash (10) so you don't have to muck about in a hex-editor yourself. (The blog was written in April, but the patch was updated in December).



I would open a browser on one screen and click Ctrl + + until the player is as big as I want it.

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