5.
Copy View as Image and crop in Preview
When you are happy with your work, do Edit > Copy View as Image, open the Mac OS program Preview, and do File > New from Clipboard:

Now change the Format to JPEG and save somewhere inside img/IMAGEMAPS. I’m using a subfolder here:

Place your crop rectangle exactly on the outside of the border:

Then hit ⌘K to crop and ⌘S to save again:
