That is good to know. I’m running an M910 RD and an M900 FD with a 6500 triple crank, but the front is still friction.
I have a set of STi shifters waiting to be installed but have been concerned that the left would not index with the M900 FD.
I did a temporary fix with a pair of Kelly Take-Offs to get the shifters up to the handlebars.
John