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The current stable of Dropbox works fine, no need to use the beta.

The beta (and all future versions) use Yosemite's new built-in support for 3rd-party storage providers to integrate with the Finder, instead of the dangerous hack used by OneDrive, Google Drive, SugarSync, etc.
 
The beta (and all future versions) use Yosemite's new built-in support for 3rd-party storage providers to integrate with the Finder, instead of the dangerous hack used by OneDrive, Google Drive, SugarSync, etc.

I am using 2.10.41 and it is already in the Extensions menu. Unless you are talking about something else.
 
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