Auto Tab Discard (ATD) is a browser extension that does what it says on the tin - automatically discards tabs after a user-specified period of inactivity. Users can exempt tabs from being discarded in two ways. First, they may provide a white list of sites whose tabs should never be discarded. Second, users can construct conditional rules based on information about the tab (e.g., Is it pinned? Playing media?) or the system (e.g., Is it plugged in to power?). Rather than building its own custom method of suspending or discarding tabs - as some other similar extensions have done - ATD relies on the native methods provided by browsers to discard tabs. ATD's author argues that using the native discard method is both more reliable and more resource-efficient than a custom method. On the top right of the page linked above, users can locate links to download the extension for Chrome, Firefox, Opera, and Microsoft Edge.