Simply activate the extension when on a thai website and then highlight words you don't know.The best Thai translator available and the only one that doesn't interrupt your reading experience. Have fun reading thai websites like pantip.com and reach fluency in weeks, not years.
I believe all software should be free which is why this extension costs only $5. Five dollars is basically free.
Don't think of it as paying for the extension; think of it as buying me a beer or a coffee or a sandwich.