Thank you for your great work, what about this warning, has it been resolved? " WARNING: we have a report that FrSky R9 receivers are not detected because of (3j) so if you are using these receivers please remain on 4.1.3 for now.
As you can see from the release notes above, the calibration code has not changed. So it is most probably a hardware issue. Is the copter hardware 100% identical? Or are they different? What are the differences?