Here's a quote from the last part of the instructions: "This is not recommended, as you are opening yourself to security problems by trusting all sites. If you ever have sensitive information in your clipboard (ie. you copy phone numbers, credit card numbers, passwords, etc), then using this is not a good idea."
First of all, I guess I'm not sure what the problem is, because I'm using Firefox, and I copied that line using ^C and pasted it here with ^V without modifying Firefox. Do I not understand the problem?
Second, a question about the recommendation. Assuming I do have sensitive information in my clipboard. Who is looking? Are they looking all the time? How can they see my clipboard? I do the checks for security at various sites and they all come back saying that my computer is essentially invisible. If my computer is invisible, how do "they" (whoever "they" is) even know I have a clipboard, let alone know what's in it? If I'm planning to paste that information into a text area, doesn't that mean that I'm about to unveil it to the world, anyway? Why else would I have sensitive information in my clipboard if I don't intend to paste it?
I guess I'm just super naive about all this security stuff.