App side menu button

Hi, in my dashboard the option “App side menu” doesn’t work…I click the button but nothing happens, why?
Thanks in advance.

Hi, this outdated setting for the old canvas, will be removed soon. Now the side menu is set to page in canvas

Hi Ruslan, thanks.
I followed the instructions on the page you pointed me to, but I still can’t get the three dots in the upper left-hand corner–I don’t understand, it’s not very simple.

In the header settings, add a button (icon) and add an action that will open your page as a side menu