Fringer just released firwmare 2.20 and they are already teasing firmware 2.30, which will add support for a very long lens the Tamron 150-600mm G2 AF. When it comes to mirrorless long glass is the only real weakness left and it’s mainly because of how specialized and expensive it can become but now that mirrorless has matured we should start to see more native long glass in the near future. Until then companies like Fringer will provide adapters for Canon and Nikon glass to be used on cameras like the Fujifilm X-T2, X-T3, X-H1 and GFX.