Problems with copying and pasting URLs

Normally, there is no problem in copying and pasting a URL. It's a procedure that ends in using the PASTE command from the EDIT dropdown menu. However, sometimes the EDIT command is not available. What do you do then?

I have an app that requires you to put the desired URL into it in order to use that URL. The problem is that when I copy the URL, I can't paste it into the app. When I am in this app, EDIT is not visible in the menu bar. I can restore EDIT by clicking on the screen, but when I do that the PASTE command in the EDIT dropdown menu is not active, it's dimmed out.

This problem only rarely occurs. Sometimes I solve it by typing in the URL, but sometimes, like now, it is too long to make that method practical. What's the solution?