Do not make unchanged lines in expanded diffs look like removed lines

[dimas]

Select Topic Area

Product Feedback

Body

When reviewing PRs and looking at diffs of large files, Github collapses large sections of unchanged code leaving only the changed lines plus few more lines around it for context. But sometimes you need to expand these collapsed blocks to get more context.

Previously, these expanded blocks were displayed on white backgound - exactly the same way as unchanged lines surrounding the change. I noticed that now these expanded blocks do have some backgound which is somewhat confusing because it looks similar to pink(-ish) backgound of removed lines.

First of all, I am not sure why these lines need to be of a different colour to the unchanged lines that are visible initially - after all, both are unchanged lines. But if it is super important for some reason - I would suggest a different way of highlighting them.