In this answer it is confirmed the possibility of using a development version of Files (the one that should be default in Loki).
Can I install that in Freya?
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It is possible to install the latest Pantheon Files if you add the daily PPA , upgrade Pantheon Files and remove the daily PPA. During the process do not attempt to update elementary OS since it would break
WARNING : You are installing development packages so they may be unstable and break your system.
sudo add-apt-repository ppa:elementary-os/daily sudo apt-get update sudo apt-get install pantheon-files sudo add-apt-repository --remove ppa:elementary-os/daily sudo apt-get update
sudo apt-get remove pantheon-files sudo apt-get remove libpantheon-files-core0 sudo apt-get install pantheon-files
As you can see the thumbnails aren't working so I downgraded to the old version.