I just submitted a smallish change. The website shows it as a humongous change because it considers every line as edited.
Presumably this must be due to line endings in some way.
I propose that the website diff ignores differing line endings and just normalises them. Otherwise the diff is just not useful.
Here is an example. https://bitbucket.org/Timwi/parsecs/changeset/65ffab8b8060#chg-Parser.cs