Add the excellent VL.LoopTool from @gegenlicht to the Gray book page on video recording (its alread on the library>animation page but I think it should also be listed on the page where you search how to capture video output)
I’m not a fan of PRs for tiny edits on gitbooks. It’s over the top.
Much faster for the author to do it themselves than review my PR, plus my time making the edit (in their style), making PR, make comment about what the PR changes etc.