It might be because I have Adblock Plus installed. More testing is needed.
This website regularly hangs and I need to delete all the Farnell cookies to get it going again. It most often happens when going to place an order but also happens at other times. After several minutes the message in Firefox is -
Secure Connection Failed
The connection to the server was reset while the page was loading.
The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
It seems to be okay with Microsoft Edge but I prefer Firefox.