Yes, I am sincere about the "stupid" part. And about the question part. And yes, I did try to find the answer - by googling and by checking on Blogger's help page and help sites. But the answers I'm finding don't seem to address the problem I'm having with Blogger on a Firefox browser. I do also have Safari, and I switch to that browser to complete posts in which this problem crops up. (I actually prefer Safari, but both browsers have different limitations that make me switch between the two. As a matter of fact, if I don't find a solution to one of my Safari problems, that will be next week's post.)
So here's the problem. When I try to do a link in a post on Blogger, a little window pops up for me to enter the URL. The idea is that I copy the URL and paste it into that little window. However, when that window pops up on Firefox, every other option on the Firefox menu at the top, including "Edit," disappears. Nor can I paste the copied item in using keyboard commands. So I usually save the post, exit, and switch to Safari.
The Firefox version I currently have is 3.6.13.
New information added on 18 January a.m.: After reading GrannyPam's comment, I decided to try the keyboard cut-and-paste option again. This time I was on my MacBook, which has both a control key and a command key - and it's the command key that is used for this function. The keyboard on my desktop computer doesn't have a "command" key, but I'll check to see if there is a key with a different label that performs this function.