The thing is: my colleague received an error after installing the plugin:
Refused to execute script from 'https://******/js/offline?' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
I cannot reproduce this error by me locally, it works as it was planned and developed. I suppose this error appears somehow only by installing on other clients.
If someone has free 10 min to install this plugin and test it a little bit, I would much appreciate your solidarity.
P.S. I am not a professional developer, that’s why this bug can be a very simple thing. I’ve googled for this issue, but could not find any useful topics.