Not sure wtf "fix" means here because this is a hard one. It looks great in unified mode
But then the vertical brace is split across both sides in split mode. I do like being able to comment on one half or the other or both, but the comment presentation in split mode needs work.
Maybe only use the brace on one side, extend it to bounds determined by both sides (lines were removed earlier in the files then added later in the file, so red extends higher and green extends lower. the brace should extend up to the red bound and down to the green bound and vice verse if they were reversed), and let the coloured asterisks indicate which lines on left or right the comment range refers to.
Or maybe there's an entirely different UX approach that would be better here 🤔 or some other way to style comments entirely that obviates the problem in both modes even.