When a help file is opened, the paragraph id fields are set to invisible. Is this the preferred way to view help files, because sometimes you can try to copy a paragraph and miss copying the paragraph id field. As a workaround for this, i created the Help Authoring > Unhide Paragraph IDs menu entry. It is possible to execute this function when a file is loaded by it causes undo entries to appear.
I think it should open with IDs and propose https://gerrit.libreoffice.org/#/c/19084/ It would be good to have a preview without any fields, but that is a different problem and should not be done by not showing the paragraph IDs on opening.
Closing as patch was pushed by Caolán.