Import library eilliptic

I'm struggling with this. I would like to import

I added it using App Settings / Libraries. There were no complaints when I hit the "Add" button (although the "Add" button seems to accept any old URL). When I log out and in, the URL is still displayed in the LIbraries page. But if I close the browser or use a different browser, the module has disappeared.

However, the JS editor does not recognise the module: "elliptic is not defined" and it doesn't show in any of the auto-fill prompts.

I have tried using Firefox and Safari.

Am I doing something wrong? Elliptic is a mature module that I have tested in node.js. I have no reason to suppose that it is faulty.

On a wider note, your documentation lacks specifics. It does not take long to find out that "import" is not supported (why?), but I had to trawl to find out that I need the .min.js version, and the Libraries part of Settings could at least complain if a URL or library doesn't meet its approval.

Thank You in Advance,