2.4.8 * Fix fatal error on the startup process for tree restored from cache. * Don't expand current tree by just hitting Ctrl key. * Don't focus to collapsed children expectedly, after the tree of tabs are restored from cache. * Don't open a new tab by right-click on the "New Tab" button. It was an unexpected behavior on Windows. * Accept `about:treestyletab-startup` as a shorthand of the startup tab. * APIs now return `indent` information as a part of extended `tabs.Tab`.