nrf connect desktop nrfconnect331x8664.AppImage and nrfconnect361x8664.AppImage install power profile fail on ubuntu 16.04

[fatalfeel]

already do preinstall https://nordicsemiconductor.github.io/pc-nrfconnect-docs/getting_started

and manual install failed

[fatalfeel]

~~~~~~~~~~I got answer
1.
from
https://nordicsemiconductor.github.io/pc-nrfconnect-docs/getting_started
https://nordicsemiconductor.github.io/pc-nrfconnect-docs/app_development
https://github.com/nodesource/distributions
curl -fsSL deb.nodesource.com/setup_16.x | sudo -E bash -
apt install nodejs
npm -v
# 7.11.2
npm install -g npm
npm -v
# 7.13.0


2. easy install (AppImage version 3.3.1)
gdown www.nordicsemi.com/.../nrfconnect331x8664.AppImage
chmod 755 ./nrfconnect331x8664.AppImage
./nrfconnect331x8664.AppImage
#if root account
./nrfconnect331x8664.AppImage --no-sandbox

3. manually install power profile
cd ~/.nrfconnect-apps/local
git clone --recursive github.com/.../pc-nrfconnect-ppk
(Tags: v2.1.0)
cd pc-nrfconnect-ppk
npm install
npm init -y  ###must do after install
npm run webpack
./nrfconnect331x8664.AppImage
#click
Power Profiler
local, v2.1.0

#all done

#ps
the error message is from "npm init"  not  after npm install