Javascript Application Error

I am being pestered when online in Firefox with this new laptop, (image below). Haven't a clue what it means and the cause. A search has not helped other than recommendations from a couple of websites to download software, i.e Total System Care. Being the wary sort thought it better to come here and ask for help.

Any advice as always will be appreciated. I'm taking a break from this frustration so please excuse me for any late response.

The error warning leaps up with each mouse click.

Javascript Application

Attached Images

jaava exception.jpg (9.4 KB)

Javascript Application Error