How old are these keys viz isn't working

The visualization at https://breckyunits.com/keyboard/# doesn't do anything in FF and Chrome on Win11.

Clicking on keyboard buttons makes them depress for a moment but that's the only visual interaction. Everything under the [Controls] heading have no apparent result.

Aside form that, thanks for the post at https://breckyunits.com/how-old-are-these-keys.html. Thought provoking.

Web developer console reports:

>jquery-3.4.1.min.js:4 Uncaught SyntaxError: Cannot use import statement outside a module (at jquery-3.4.1.min.js:4:1)
>jtree.browser.js:6918 Uncaught SyntaxError: Cannot use import statement outside a module (at jtree.browser.js:6918:1)
>keyboard.browser.js:202 Uncaught SyntaxError: Cannot use import statement outside a module (at keyboard.browser.js:202:1)
>keyboard.js:111 Uncaught SyntaxError: Cannot use import statement outside a module (at keyboard.js:111:1)

Start by loading the keyboard visualization in Firefox or Chrome and inspect the console errors for jquery-3.4.1.min.js, jtree.browser.js, keyboard.browser.js, and keyboard.js. Trace the reported import errors and verify that keyboard buttons and the controls produce their intended visual interaction without console syntax errors.

Written by the indexing model from the issue text.