2.4.23 * Add [new API to notify sidebar is shown or hidden](https://github.com/piroor/treestyletab/wiki/API-for-other-addons#when-the-tst-sidebar-is-shownhidden) for other addons. * Apply correct favicon for restored tabs. * Fix freezing after a tab is detached from a window by drag and drop. * Make tabs more easily detachable by drag and drop.