On our version of NodeBB (v1.17.2) which uses the Redactor plugin for text entry, clicking the Redactor's Video button to embed a video, the dialog that opens suggests:
Video Embed Code or YouTube/Vimeo Link
But if you actually enter the embed code from Vimeo, it messes up the post to the point where the user can no longer edit it.
On the other hand, a YouTube or Vimeo link by itself works fine.
I know Redactor is no longer supported, but do you have any idea how we could fix this issue?