Doesn't work on mac OS Sierra 10.12

[dieucode]

I installed it with the terminal in the user folder, then moved it manually in the system folder, relanched the finder, restarted the computer, it still does not work.
I tried that command and there was no such file.
xattr -d com.apple.quarantine /System/Library/QuickLook/WebpQuickLook.qlgenerator