Safari has been frustratingly aggressive for me. I was working with a fairly heavy Google Spreadsheet and Safari would need to refresh/reload every time it lost

Safari has been frustratingly aggressive for me. I was working with a fairly heavy Google Spreadsheet and Safari would need to refresh/reload every time it lost focus. Between Chrome, Firefox, Safari and their plugins it's a dance to get the desired behavior and efficiency. Lazy loading of pages (when you have multiple tabs and close/reopen) can either be really efficient (because they don't even load the page) or annoying (if you don't have Internet or they change/remove the page when you go back to read it).