Interesting, that just seems like a gitweb bug? If you click tree on the master branch it works, wonder if my default branch is misconfigured.
Discussion
Yup, this links works: https://git.bitcoin.ninja/index.cgi?p=lightning-resolver;a=tree;h=refs/heads/master;hb=refs/heads/master
I think it could be a bug, the tree link could be missing a reference to a branch.