Hi

Thanks for contacting us. You can use this custom CSS

#offcanvas-toggler:after{
  display:none !important;
}

Go to system--> https://prnt.sc/tDbSUJh6LiGu --> Default template-->Template options--> https://prnt.sc/A5nlsBvCQsqs And add your CSS there.

-Regards.

If I may...

Those dots were added by You or somebody who built that site before you. It's not a part of Helix template code, and I can prove it quickly.

In Template Options > Custom Code > Custom CSS find that part

#offcanvas-toggler::after {
  content: '⁝';
  color: white;
}

and DELETE it > Save settings.