See: https://support.mozilla.com/en-US/forum/1/706123?

I am having the same problem with a similar computer setup. Norton warning comes up that Firefox plug-in container using 64% of CPU. Online Flash game no longer responds.

Works fine using Internet Explorer. I have updated Firefox and Flash plug-in but didn't help.

The link in the reply above doesn't exist (Page Not Found).

I am only an ordinary user and can not edit others posts but I suspect the link should be https://support.mozilla.com/en-US/questions/706123 , although that is rather a long and meandering thread, and I am not sure exactly which post the op found to be the solution.

I would comment that the Norton warning is only that something is using CPU resources.

• You can prevent Norton flagging that particular process, but it may well then flag up something else unless the warning is disabled entirely
• The plugin container using the resources will be running a plugin such as FlashPlayer. If you are running high resolution and high bandwidth video it may not be unexpected that it is consuming a lot of resources.

It may be worth starting your own thread if you want answers regarding your own specific problem. If you do start a new thread I suggest you try to make use of the options offered to include system information as you create the question.

• See also Firefox uses too much memory or CPU resources - How to fix

It is also a good idea to check the computers specification, and compare it with the specifications

• required as a minimum
• recommended

by any plugins that are used. Remembering in the case of videos that there are many variables to be considered regarding quality, resolution , codecs etc