install of websocket and immediatly disapear

[pedefe]

Hello.
I use websocket module on multiple project without problem.

Now, I try to reinstall an existing project on a new linux computer, and to add each nodejs module manualy.

Now comes "websocket" module.

As you see below, the last version is downloaded, but no trace of it, nor in NPM package.json, nor in node_modules folder, nor at run

root@bionic-newport:~/NexoManager# npm install -g websocket --save --unsafe-perm
+ websocket@1.0.34
updated 1 package in 5.706s
root@bionic-newport:~/NexoManager# npm ls websocket
NexoManager@1.0.0 /root/NexoManager
`-- (empty)

root@bionic-newport:~/NexoManager#  node index.js
...
> var ws = require("websocket")
Uncaught Error: Cannot find module 'websocket'
Require stack:
- <repl>
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:815:15)
    at Function.Module._load (internal/modules/cjs/loader.js:667:27)
    at Module.require (internal/modules/cjs/loader.js:887:19)
    at require (internal/modules/cjs/helpers.js:74:18) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [ '<repl>' ]
}

Install with verbose option gives:

root@bionic-newport:~/NexoManager# npm install -g websocket --save --unsafe-perm --loglevel verbose
npm info it worked if it ends with ok
npm verb cli [
npm verb cli   '/usr/local/lib/nodejs/node-v12.21.0-linux-arm64/bin/node',
npm verb cli   '/usr/local/lib/nodejs/node-v12.21.0-linux-arm64/bin/npm',
npm verb cli   'install',
npm verb cli   '-g',
npm verb cli   'websocket',
npm verb cli   '--save',
npm verb cli   '--unsafe-perm',
npm verb cli   '--loglevel',
npm verb cli   'verbose'
npm verb cli ]
npm info using npm@6.14.17
npm info using node@v12.21.0
npm verb npm-session 87675b24ee6b3ebc
npm http fetch GET 304 https://registry.npmjs.org/websocket 1188ms (from cache)
npm timing stage:loadCurrentTree Completed in 1823ms
npm timing stage:loadIdealTree:cloneCurrentTree Completed in 14ms
npm timing stage:loadIdealTree:loadShrinkwrap Completed in 80ms
npm http fetch GET 304 https://registry.npmjs.org/bufferutil 533ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/es5-ext 570ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/debug 703ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/utf-8-validate 719ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/typedarray-to-buffer 739ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/yaeti 1186ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/node-gyp-build 226ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/ms 206ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/next-tick 307ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/es6-iterator 335ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/es6-symbol 354ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/d 202ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/type 222ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/ext 185ms (from cache)
npm http fetch GET 304 https://registry.npmjs.org/is-typedarray 197ms (from cache)
npm timing stage:loadIdealTree:loadAllDepsIntoIdealTree Completed in 3154ms
npm timing stage:loadIdealTree Completed in 3322ms
npm timing stage:generateActionsToTake Completed in 49ms
npm verb correctMkdir /root/.npm/_locks correctMkdir not in flight; initializing
npm verb lock using /root/.npm/_locks/staging-e3e75e99a08fb154.lock for /usr/local/lib/nodejs/node-v12.21.0-linux-arm64/lib/node_modules/.staging
npm timing action:extract Completed in 246ms
npm info lifecycle websocket@1.0.34~preuninstall: websocket@1.0.34
npm info lifecycle websocket@1.0.34~uninstall: websocket@1.0.34
npm verb unbuild rmStuff websocket@1.0.34 from /usr/local/lib/nodejs/node-v12.21.0-linux-arm64/lib/node_modules
npm info lifecycle websocket@1.0.34~postuninstall: websocket@1.0.34
npm timing action:unbuild Completed in 25ms
npm timing action:remove Completed in 133ms
npm timing action:finalize Completed in 62ms
npm timing action:refresh-package-json Completed in 41ms
npm info lifecycle websocket@1.0.34~preinstall: websocket@1.0.34
npm timing action:preinstall Completed in 5ms
npm info linkStuff websocket@1.0.34
npm timing action:build Completed in 9ms
npm info lifecycle websocket@1.0.34~install: websocket@1.0.34
npm timing action:install Completed in 5ms
npm info lifecycle websocket@1.0.34~postinstall: websocket@1.0.34
npm timing action:postinstall Completed in 5ms
npm verb unlock done using /root/.npm/_locks/staging-e3e75e99a08fb154.lock for /usr/local/lib/nodejs/node-v12.21.0-linux-arm64/lib/node_modules/.staging
npm timing stage:executeActions Completed in 617ms
npm timing stage:rollbackFailedOptional Completed in 2ms
npm timing stage:runTopLevelLifecycles Completed in 5833ms
+ websocket@1.0.34
updated 1 package in 5.851s
npm verb exit [ 0, true ]
npm timing npm Completed in 8015ms
npm info ok
root@bionic-newport:~/NexoManager#

What happends ?

Best regards.