selection of form fields uisng tab on Mac

By default, form field selection on Mac using tab doesn't work. To do this go to System Preferences ---> keyboard ---> and then select "All Controls" for "Full keyboard access: In windows and dialogues, press Tab to move keyboard focus between:".

By default Text boxes and lists only is selected as shown in the picture below. Just select "All controls" and then you'd be able to use Tab and Space bar combination to focus and select equivalent to moving mouse onto the option and left clicking.

In the picture below you can see that cancel option is focused and you can hit the space bar to select this option to cancel deleting the song from iTunes.