Add a new option --spider-output
I was talking to user Trashpanda on #wget who suggested the addition of this flag to Wget2. The idea is to have Wget2 output a file with all the URLs it accessed as part of executing a --spider run. This is useful for complicated recursive retrieval scenarios or even for people to create a local sitemap.
It's an often requested feature which I think would be nice to have for Wget2.