This version remains a popular choice for its balance of stability and performance. Key features include:

Released in early 2021, this specific version was one of the first to provide stable, non-beta support for Big Sur’s new system architecture. It introduced essential workarounds for Apple's heightened security model, which required users to manually grant "Full Disk Access" to several background services—specifically , fctservctl , fmon , and fmon2 —just to make the VPN and Antivirus features function. Key Technical Highlights

FortiClient 6.4.3 remains a pivotal version for Mac users, particularly those managing transitions between older macOS versions and the modern macOS Big Sur

: Seamlessly connects with FortiOS 5.6 and later versions.