See this article for information on Final Draft compatibility on various Mac operating systems: Which version of Final Draft can I run on which operating system?
If you have FD12 or 11, open Final Draft and go to Help > Check for Updates. If you're prompted to update, follow the screens to get the new build installed. Your scripts will not be affected by the update.
Final Draft 10 and older are no longer supported, and cannot be installed or updated. You can purchase an upgrade to a later version of Final Draft by clicking here.
Your scripts will not be affected by installing the newer build.
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