New system for displaying older versions
Due to the rapid releases from the Chrome and Firefox browsers, the original system for displaying previous versions in the compatibility tables has started to become less practical. Specifically not being able to show Firefox 3.6 using this system has become a problem, since it still sees significant user share.
The new system shows only versions based on a (customizable) usage share percentage, based on information from StatCounter or from imported data. Current and future versions will always be visible, since that information should be helpful regardless of user share. Additionally, mobile versions will always be shown by default, since their share is currently quite a bit lower from desktop browsers.
To customize the versions shown, click Show options at the top left of the Tables tab, then under Versions shown drag the slider to change the threshold set for versions shown. Setting it farther to the right will increase the percentage of users required for a version to appear. Sliding it all the way to the left will result in all versions being visible. Note that "Total users not shown" will show the total percentage of users being hidden.
The options mentioned above are stored in localStorage, so returning to the site will keep the last used settings.
I hope this change will help developers in targeting only the older versions that matter, while providing the freedom to determine specifically at which point they do or do not.