Upgrading from 2.2.x

2.3.0 replaces the toolbar but keeps the PHP API. Panel classes extending DebugPanel, their elements, the component settings, DebugTimer, DebugMemory, DebugKitDebugger, FireCake and the ToolbarAccess controller keep working. Behaviour changes:

• The toolbar is shown in an iframe in the bottom right-hand corner instead of being rendered into the page, and it is inserted on Controller.shutdown instead of View.afterLayout. Pages rendered without a layout now get the toolbar too, as long as they are HTML and have a </body> tag.
• HtmlToolbarHelper::send() does nothing anymore; ajax and non HTML requests still use FirePHP (FirePhpToolbarHelper) as before.
• The request history is kept in the request history storage (tmp/debug_kit.sqlite) and is shared by all clients instead of being kept per user agent in the cache. The History panel content changed accordingly. The legacy cache state is still written, ToolbarComponent::loadState() and ToolbarAccessController::history_state() are deprecated.
• webroot/js/js_debug_toolbar.js and webroot/css/debug_toolbar.css were removed, the toolbar uses webroot/css/style.css and webroot/js/main.js. The default values of ToolbarComponent::$javascript and ToolbarComponent::$css are now empty arrays; they list additional assets loaded into the toolbar iframe.
• The toolbar no longer ships jQuery, nor the DEBUGKIT JavaScript API of the 2.x toolbar (DEBUGKIT.module(), DEBUGKIT.loader, DEBUGKIT.$, DEBUGKIT.Util.Cookie, ...). Panel css/javascript files (DebugPanel::$css, DebugPanel::$javascript) are still loaded into the toolbar iframe, but panel JavaScript must not rely on jQuery or the old API: bundle what it needs and use the initPanel event (see Panel Elements) instead of DEBUGKIT.loader.register().
• The built-in elements no longer print their own <h2> title, the toolbar shows the panel title.
• ToolbarHelper::getQueryLogs() no longer clears the query log of the connection.
• The debug_kit connection is not listed by the Sql Log panel.