On a couple of old spec legacy machines I recently switched. 
Partly because of economics,  and partly because ,  of the two, 
 Norton can perform  better (in my opinion) on legacy machines. 

Probably the alerts are nothing to worry about, and you may wish to suppress that particular alert. On a couple of old spec legacy machines I recently switched. <br>Partly because of economics, and partly because , of the two, <br> Norton can perform better (in my opinion) on legacy machines. The first thing I did notice was that Norton does pulse updates and background tasks very frequently (configurations can be changed) by default, and flags up quite a number of alerts. The Norton (NIS) 'Insight' facility will be flagging up firefox plugin container.exe. It can be configured to suppress the alerts from firefox plugin container, but unless disabled will probably just flag up another busy process or application. It is not flagging it up because it is a known security problem, merely because of the amount of activity. I imagine the alerts are when you are playing videos, probably with FlashPlayer, and may well depend on the resolution/quality of the videos. If you think the results are unusual or unexpected see: *[[High memory usage]] *[[Firefox consumes a lot of CPU resources]] PS not sure what is happening with this post are some phrases unacceptable eg alternative expressions about economics; one paragraph was behaving oddly in preview resorted to manually adding break tags to keep it within the container.