Hi,

1. Problem can be caused by too strong JS compression
2. But as first step, please read tip No 1 from >> https://www.joomshaper.com/documentation/helix-framework/helix-ultimate-2/troubleshooting-faq
3. Disable JS compression from Template Options, use only from plugin if any.

We're getting an error of being unable to save any changes. Please advise says: Error : Undefined.

In that case we need access to back-end as Super User.

Logins in hidden section

G’day, checking ...

No Worries, fixed.

I had to only move your custom JavaScript from Template Options to extra installed Phoca Site plugin. It has also Joomla 4 version, tip for the near future. Yes, of course now Template Options saves without any error message and Mobile menu works. At least worked 90sec ago...