Why Are 2 Plugin-Container.Exe Processes Running?
I recently discovered that I had two explorer.exe processes running on a Windows PC. Odio posted a comment under that article where he mentioned that on his PC 2 plugin-container.exe processes were running instead. If you do not know anything about plugin-container.exe you can check out the informational article about it that I wrote in 2010.
Plugin-container.exe is Mozilla's implementation of separating core plugins from being executed in the same process as the Firefox web browser.
This is done foremost to improve stability. A plugin crash previously would have often caused the whole browser to crash as well. With plugins moved to plugin-container.exe the browser remains unharmed if a crash happens.
Back in 2010 Firefox used one instance of plugin-container.exe for the three plugins Adobe Flash Player, Microsoft Silverlight and Apple Quicktime.
Firefox users nowadays may see more than one instance of the plugin container process on their system and some may wonder why that is the case. The idea from the very beginning was to move core plugins into their own process eventually, and that's what has been integrated into the browser now.
You can test it on your system easily. Make sure you have the Adobe Flash and Microsoft Silverlight plugin enabled. Visit YouTube and start watching a video to trigger the Flash plugin-container.exe.
Now open a new blank tab and visit a site that uses Microsoft's Silverlight technology to play videos. You will notice that plugin-container is launched twice and that the processes stay open when the video stops playing and even if the page is closed.
Not all plugins will be launched in their own plugin-container.exe process. If you launch a Java application you will notice for instance that it is not launched in its own plugin container process.
Firefox users can disable plugin-container.exe completely in the advanced configuration of the browser. Enter about:config in the address bar and hit enter. Now filter for the following term and set their values to false to disable the feature.
You can also disable separate processes for a specific supported plugin instead.
- dom.ipc.plugins.enabled.npctrl.dll (Microsoft Silverlight)
- dom.ipc.plugins.enabled.npqtplugin.dll (Apple QuickTime)
- dom.ipc.plugins.enabled.npswf32.dll (Adobe Flash)
- dom.ipc.plugins.enabled.nptest.dll (NPAPI test plugin)
Many Firefox users are reporting issues that they have with plugin-container.exe all over the Internet. What is your experience with Firefox's out of process plugins?
Update: You may also see a FlashPlayerPlugin process (or two) in the task manager when you run Flash contents in recent versions of Firefox. If you see it, Flash Player Protected Mode is enabled, if you see plugin-container.exe instead, it is disabled.Advertisement