Mobile menu opens — but doesn’t CLOSE

Both wordpress & twentytwenty both up to date (2020-02-18)

1. click the “…” menu button:
—>> menu opens, “modal” mode.

2. click on any menu item that links to an #id on the current page:
—>> nothing happens, and no errors in the JS console.

4. click again the “…” menu button.
—>> the menu closes, and only then the page scrolls to the location.

Expected behavior:
When user clicks any menu item, the menu closes, and page scrolls to element.
I don’t know it ever worked as expected.

what I tried
I added a JS event, manually from the console, to trigger the menu close upon menu click. it closes, scrolls to the location, but then also scrolls back to top (probably to the element that was artificially clicked).

The page I need help with: [log in to see the link]