bug#61396: diff mode could distinguish changed from deleted lines

[Juri Linkov]

>   -this is a line that ^looks deleted, but it is changed
> ...
>   +this is a line that REALLY looks deleted, but it is changed
>
> what is not indicated for the user is at the ^.  i would like it if
> diff mode if possible showed that text was deleted there.

Thanks for the feature request, this would be a very useful feature.
There is already a TODO item for implementing it:

  (defun smerge--refine-highlight-change (beg match-num1 match-num2 props)
    ;; TODO: Add a property pointing to the corresponding text in the
    ;; other region.

Maybe Stefan could suggest a hint on how better to proceed.