...and changed the filament runout procedure
Druing the print you can access the Tune menu and the new feature Power Mode [auto] was added, but choosing it it goes to the Settings menu. Here the fix for that in the ultralcd.cpp.
Also changed the filament runout procedure in Marlin_main.cpp to use M600 command (origin idea/update from Marlin 1.1.x) defined in the 1_75mm_MKx_yyyy_E3dv6full.h files
Updated to: 3.1.0-RC1
Some of the format changes introduced were done to improve readabilty and
remove compiler warnings about needing parenthesis
Some code restructuring has been done to eliminate unused code and variables
Cleanup defined but unused functions