FlashOptimizer 2.3 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available.
Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. The software lies within Developer Tools, more precisely Webmaster Tools. The actual developer of this software for Mac is DoSWF.
From the developer:
FlashOptimizer is a tool to optimizer Adobe SWF file(just based on Actionscript3.0).
You may want to check out more Mac applications, such as Flash Optimizer 2, which might be similar to FlashOptimizer.