Flash Builder 4.6 was the most stable and feature-complete version of the IDE. It proved that the Flex framework could handle the demands of the mobile revolution. However, its legacy is tied to the industry's shift away from browser plugins toward HTML5.
Adobe Flash Builder 4.6 was inseparable from the Flex 4.6 SDK. The two were version-locked for stability. Flex 4.6 introduced the , replacing the older MX components.