The tab manager called Panorama groups tabs into graphical sets just by dragging and dropping. Clicking one tab will only show tabs within the group instead of having many tiny tabs displayed on the browser.
Firefox Sync, meanwhile, synchronizes bookmarks, passwords, browser history, open tabs and other data across multiple computers and devices. This function is actually available in earlier Firefox versions through an add-on and on iPhones via the free Firefox Home app.
Computers running on Windows Vista and Windows 7 allow the improved browser to activate the hardware accelerator by editing the "about:config" file based on instructions posted on the Mozilla site. The Windows' Direct2D API (application programming interface) lets the graphic processor work instead of the central processor in page rendering.
Firefox 4 is set for release in October and shipping starts November. The beta version is available in 35 languages and is also downloadable for M ac and Linux operating systems.