Trouble installing the ARChon Runtime Extension for Google Chrome

I want to install the ARChon extension. I followed the guidelines saying "go to 'chrome://extensions' and turn on developer mode, and load unpacked". When I do that, it successfully pops up like all the other extensions, but it has a 'reload' button, and sometimes two warnings (that I just ignored). For it to work I thought I should click the button, but it just magically disappears. However if I don't click the button, the extension is just not working.

This is what Google Chrome on Mac OS Catalina shows:

Version: 38.4410.120.43
Size: 273 MB
ID: mfaihdlpglflfgpfjcifdjdjcckigekc
Loaded from: ~/Downloads/vladikoff-archon-6ad1d59d5f1a

Could anyone please explain how this works, and / or tell me how to fix it? Thanks in advance

This is a screenshot of how it looks:

[need-help]