Cursor makes strange jumps during navigation

[den1k]

I'd expect this behavior

abc
d|ef

;; press arrow up

a|bc
def

Instead it jumps around! Sometimes to the end of the line, sometimes to the previous cursor column in a the navigated-to line. And sometimes it just works albeit with little quirks:

video: https://cln.sh/Mfuh6i

[mhuebert]

Agree, vertical movement is broken & should be fixed