Diff does not show correct position in some situations

[astares]

The diff shown by the following expression (which is coming from a diff change where a space got removed)

SpDiffPresenter new
        showOptions: false;
        leftText: 'ABC. ';
        rightText: 'ABC.';
        open

looks like:

where the red bar is behind the dot - but it is the space which is the difference. So the red bar should be one single position behind the dot and the expected behavior would be the diff would look like:

[astares]

If one does not use a dot but a # character it is even more strange as the red bar is not even shown:

SpDiffPresenter new
        showOptions: false;
        leftText: 'ABC# ';
        rightText: 'ABC#';
        open

as if nothing had changed.

[astares]

Initially I thought because left input string is longer than the right input string.

But there are other examples where it does not display correctly when the size is same:

SpDiffPresenter new
        showOptions: false;
        leftText: 'ABC.#';
        rightText: 'ABC#.';
        open

which shows a change only for the first four positions - but it has changed on the fourth and fifth character position:

when you do not use a dot but an underline you get a different position coloring:

SpDiffPresenter new
        showOptions: false;
        leftText: 'ABC_#';
        rightText: 'ABC#_';
        open