What may have happened to my Norton Toolbar?

After I upgradeg from NIS2009 to NIS2010, a week or two ago, I automatically started seing the Norton Toobar at the top of my Mozilla Firefox web browser and I particularly liked that green check safemark that Norton would attach to the title of each web page, following a Google search request.

 

To my surprise, today I stopped seeing those checkmarks and noticed that the Norton Toorbar wasn't listed there any longer If I check the Tools tab and click Add-ons, Norton Toolbar 4.0 is listed and the button "Disable" is highlighted, suggesting that the add-on is enabled.

 

I'm running on Windows Vista Home Premium and have the most recent update of Firefox (Version 3.5.4).

 

I had got used to those safemarks and would like to see them again but I do not know how to get them back.Could anyone kindly show me the way to do this? 

 

Thanks in advance for any help.