An error in the log of the page "pages-sign-in.html" also signup page of your template is visible in the console log with the following stack trace:
link : https://demo.adminkit.io/pages-sign-up.html

Uncaught TypeError: Invalid value used as weak map key
    at WeakMap.set (<anonymous>)
    at t.e.init (simplebar.esm.js:401)
    at new t (simplebar.esm.js:354)
    at HTMLDocument.<anonymous> (sidebar.js:6)

this causes crashes in javascript sometimes.
browser is the brand new chromium edge, tested also on google chrome same error "Invalid value used as weak map key"