>>2044786
I don't know what to tell you, I literally switched the derailleur and could reliably reproduce the phenomenon Only the derailleur was switched, nothing else
Spin the wheel (and cassette) up to speed in a high gear and stop turning the pedals
The top run of the chain bunches up and is at very high risk of getting jammed between the rive side chainstay and the chainwheel
Switch to a clutched derailleur and the issue is gone
The actions are the exact same as the shitmano m4120 derailleur