Apple’s Mail app is great about auto-encoding text that starts with
http://, making it easy to just click and load the URL in your browser. But what if you want to copy a portion of the URL instead? Using the contextual menu, it’s easy to copy the entire URL (control-click on the URL and choose Copy Link), but any attempts to click-and-drag in the middle of the URL just result in dragging the URL.
The secret? Hold down the Command key before you click-and-drag the mouse over the portion of the URL you’d like to copy. It takes a bit of practice and good timing, but it does work reliably. Make sure you start dragging immediately after you click-and-hold the mouse button down. If you delay the drag at all, you’ll wind up dragging the full URL. Once you’re sure that you’re selecting a portion of the URL, you can release the Command key—you don’t need to hold it down while you select the text you’re interested in copying.
Once the text is selected, just press Command-C to copy it to the clipboard, then paste it wherever it was you wanted to use it. You can also drag the portion of text you highlighted—as long as you’re holding down the Command key (press and hold it again if you released it while dragging). If you forget about the Command key, as soon as you start dragging, you’ll drag the entire URL.