[Guillaume Barreau]

I had the same problem and from that link

https://gdlp01.c-wss.com/gds/7/0300003887/02/XFPLUGIN-FCP_12_M_EN.pdf

found that the reason was that the Canon XF Mpeg2 Decoder was not installed. I read somewhere else that this could be solved by installing the Canon XF utility which I did.

And then it worked.

Guillaume