In bug #83877 the Writer -> Insert -> Signature Line dialog has been added. Let's not forget to document it before 6.1 once the actual work is finished there :).
Olivier Hallot committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/help/commit/?id=28138ff018a1ee48dc659b6d0ef0073b0a00a14e tdf#115599 Add signature line help page
Clicking Help in Writer -> Insert -> Signature Line dialog in 6.2+ doesn't invoke help page. Is it this bug?
(In reply to Timur from comment #2) > Clicking Help in Writer -> Insert -> Signature Line dialog in 6.2+ doesn't > invoke help page. > Is it this bug? Should be a different one. The commit in comment #1 (seemingly) correctly added this line: + <bookmark xml-lang="en-US" branch="hid/cui/ui/signatureline/SignatureLineDialog" id="bm_id581526498170919" localize="false"/> This should do the trick, at least in theory - so please open a new bug if it still does not work.