Fourth line should be:

cd /root/TRIGGERcmd-Agent

I think that's how it download file.

Is this normal?

root@fox:~/TRIGGERcmd-Agent# npm install
npm WARN deprecated chokidar@1.7.0: Chokidar 2 will break on node v14+. Upgrade                                   to chokidar 3 with 15x less dependencies.
npm WARN deprecated request@2.88.2: request has been deprecated, see https://git                                  hub.com/request/request/issues/3142
npm WARN deprecated posix-argv-parser@2.0.0: No longer maintained
npm WARN deprecated gulp-util@2.2.20: gulp-util is deprecated - replace it, foll                                  owing the guidelines at https://medium.com/gulpjs/gulp-util-ca3b1f9f9ac5
npm WARN deprecated gulp-util@3.0.8: gulp-util is deprecated - replace it, follo                                  wing the guidelines at https://medium.com/gulpjs/gulp-util-ca3b1f9f9ac5
npm WARN deprecated react-tools@0.13.3: react-tools is deprecated. For more info                                  rmation, visit https://fb.me/react-tools-deprecated
npm WARN deprecated fsevents@1.2.13: fsevents 1 will break on node v14+ and coul                                  d be using insecure binaries. Upgrade to fsevents 2.
npm WARN deprecated har-validator@5.1.5: this library is no longer supported
npm WARN deprecated chokidar@2.1.8: Chokidar 2 will break on node v14+. Upgrade                                   to chokidar 3 with 15x less dependencies.
npm WARN deprecated core-js@1.2.7: core-js@<3 is no longer maintained and not re                                  commended for usage due to the number of issues. Please, upgrade your dependenci                                  es to the actual version of core-js@3.
npm WARN deprecated buffer@2.1.13: This version of 'buffer' is out-of-date. You                                   must update to v2.8.3 or newer
npm WARN deprecated circular-json@0.3.3: CircularJSON is in maintenance only, fl                                  atted is its successor.
npm WARN deprecated core-js@2.6.11: core-js@<3 is no longer maintained and not r                                  ecommended for usage due to the number of issues. Please, upgrade your dependenc                                  ies to the actual version of core-js@3.
npm WARN deprecated urix@0.1.0: Please see https://github.com/lydell/urix#deprec                                  ated
npm WARN deprecated minimatch@0.3.0: Please update to minimatch 3.0.2 or higher                                   to avoid a RegExp DoS issue
npm WARN deprecated resolve-url@0.2.1: https://github.com/lydell/resolve-url#dep                                  recated
npm ERR! code EBADPLATFORM
npm ERR! notsup Unsupported platform for node-windows@0.1.14: wanted {"os":"win3                                  2","arch":"any"} (current: {"os":"linux","arch":"x64"})
npm ERR! notsup Valid OS:    win32
npm ERR! notsup Valid Arch:  any
npm ERR! notsup Actual OS:   linux
npm ERR! notsup Actual Arch: x64

npm ERR! A complete log of this run can be found in:
npm ERR!     /root/.npm/_logs/2020-10-23T21_32_13_991Z-debug.log
root@fox:~/TRIGGERcmd-Agent#

I will try as soon as I get some free time and I will get back to you. Thanks for reply.

@Russ I am using ubuntu server 20.4 on proxmox vm to test. And yes from server to x-windows.. tried twice and happened both time.

@Russ I will try but why is it switching to GUI version of my install from headless I had initially?

@Russ Not working for me. I did all your steps, but I am getting this on final check:

https://imgur.com/QHDUV8q.

And it was server when I installed base system for VM, but after all this command, it turn to GUI and can't open terminal anymore.