NewLeaf (as in clock time, not as in numbers) extracts data from YouTube pages.
CloudTube provides interfaces to display that data, like a video player, search listings, channel views, and subscription management. It can use either NewLeaf or Invidious to initially collect that data.
A hosted CloudTube+NewLeaf is available at https://tube.cadence.moe for everyone to try.
The mailing lists and ticket trackers here collect issues for both repositories, so that users do not need to know the technical details of where the bug was generated and where to report it, since all issues are initially reported in one place.