Incorrect documentation of optional feature example (conceal) in usr_02.txt

[krishnakumarg1984]

Problem

The documentation page of user-manual usr_02.txt says:

24) Optional features always start with "+".  To find out about the
       conceal feature use: >
	:help +conceal

However, this given example does not work at all and produces an error message

E149: Sorry, no help for +conceal

Steps to reproduce

nvim --clean.
:help +conceal

Expected behavior

Unsure if the optional features help feature (and documentation) is present in neovim?

Neovim version (nvim -v)

NVIM v0.10.0-dev-3107+g8c7a8be27

Vim (not Nvim) behaves the same?

no, vim 9.1.0200

Operating system/version

Linux Ubuntu 22.04

Terminal name/version

wezterm 20240203-110809-5046fc22

$TERM environment variable

xterm-256color

Installation

bob (package manager) nightly