Once you are done, click on output, use "Ctrl+A, Ctrl+C" and paste it on your destination file.(You may not see all text selected, but it will Copy/paste works as needed)
Paste your uncompressed HTML in the first textbox and click on button "Minify HTML", wait for few seconds and you should get minified HTML in the second text-box, copy it and use it to save your server bandwidth for free.