Uncaught Error: Bootstrap tooltips require Tether

I've created an ASP .Net Core 1.1 MVC web app, and I notice that when I run it, and I look at the developer tools in my web browser (F12), it complains about this:

Uncaught Error: Bootstrap tooltips require Tether (http://tether.io/)
    at bootstrap.js:2749
    at bootstrap.js:3350
    at bootstrap.js:3535

I looked in the "Bower" folder under "Dependencies" in the Solution Explorer (Visual Studio 2017), and I only saw bootstrap (4.0.0-alpha.6) and not tether. The funny thing is, when I right-clicked and selected "Manage Bower Packages", it showed tether as being installed. So I proceeded to uninstall it and re-install it. Now I do see "tether (1.4.0)" in the "Bower" folder of "Dependencies". However, I am still getting the same error in the console of my web browser (both Edge and Chrome).

My bower.json file looks like this:

 {      "name": "asp.net",      "private": true,      "dependencies": {        "jquery": "3.2.1",        "jquery-validation": "1.16.0",        "jquery-validation-unobtrusive": "3.2.6",        "bootstrap": "v4.0.0-alpha.6",        "tether": "v1.4.0"      },      "resolutions": {        "bootstrap": "v4.0.0-alpha.6",        "jquery": "3.2.1",        "jquery-validation": "1.16.0"      }    }

Any ideas? I did see somewhere that bootstrap requires tether, so tether should be listed first. So I swapped the order of bootstrap and tether around, to no avail. I did try some other suggestions from other similar posts on this forum, but most I either didn't understand, or don't seem to apply to ASP .Net?

Any ideas? Thanks...