In Safari 7 on Mavericks, loading a diff longer than can be displayed breaks scrolling.

e.g. URL will be something like:
http://stash.domain.example./projects/PROJECT/repos/project/pull-requests/1/diff
or:
http://stash.domain.example./projects/PROJECT/repos/project/commits/h4sh#file.name

The scroll bar will appear as you try to scroll, but the bottom of the file never moves into view. Disabling javascript does not fix the issue (you seem to have forgotten the mantra of "progressive enhancement").

Works as expected in Chrome 34, though I wouldn't call being told to use a different browser a work-around, hence I have made this a Major issue.