Pull request diff contrast improvements

As of Bitbucket Server 7.0, the updated pull request diffs use a defined font stack, as well as some updated colors. This means that users that previously had a font defined that improved their ability to read code now have to resort to CSS hacks to improve the legibility of code views on the pull request.

Bitbucket Server could add an option to make the diff views more accessible by one or more of the following options:

• Allowing to switch back to the monospace font family so users can control the font used
• increasing the font size and line-height
• improving the contrast of the color scheme used for diff views.