Webots 8.5.4 fixes a few bugs, including issues with the e-puck robot window, Radar
devices, logout functionality and a couple of rare crashes. It also improves the performance of some supervisor functions and introduces the ability to rotate an object with the mouse around the world vertical axis. It is recommended to all users of Webots 8 to proceed to this upgrade.
The complete change log is available here
. Download Webots 8.5.4 now from here