I like you're thinking here @Esanders - before making any pattern changes, I would want to explore how we are handling visual diffs in general. Do you have particular visual diffs that you like that you can screenshot as an example?

If you enable the visual diff beta feature in your preferences you will be able to see visual diffs at links like this:

https://en.wikipedia.org/w/index.php?title=Daniel_McCallum&diff=prev&oldid=1001780327&diffmode=visual

Here we would replace/augment the vertical ellipses (⋮) to make them clickable:

Similar to the expand buttons you get in the gutter on GitHub:

https://github.com/MatmaRex/patchdemo/commit/638afd2fe0bdd999a88d332383608c059cd2ae9c

Change 755514 had a related patch set uploaded (by Esanders; author: Esanders):

[VisualEditor/VisualEditor@master] WIP Show diff context when clicking on spacers

https://gerrit.wikimedia.org/r/755514

Change 755515 had a related patch set uploaded (by Esanders; author: Esanders):

[mediawiki/extensions/VisualEditor@master] MWSaveDialog: Reposition diff element when it resizes

https://gerrit.wikimedia.org/r/755515

https://patchdemo.wmflabs.org/wikis/b87bc5fb0d/w/index.php?title=Douglas_Adams&type=revision&diff=33&oldid=19&diffmode=visual