I was curious about trying out my own diff so I went to the home page: https://www.difflensapp.com/ and didn't see an option.
It would be interesting to be able to append a github compare / pr / tree-ish link to see the diff via difflens, so maybe something like:
https://www.difflensapp.com/github.com/rails/rails/commit/7d...
would render that diff via diff lens. just an idea to get more people testing.
Please change the title to something like "DiffLens: Language Aware Diffs on GitHub Pull Requests". It's fine to post your stuff here, but it's better that it's clear that it's a post and not a question.
About the project: It was difficult to understand what it is doing looking at the 3 screenshots in the page. After a few hops I reached the demo https://www.difflensapp.com/difflensDemo2_849ca26f9ee09faa08... that is easier to understand.