I have checked and this problem with the X icon is happening also in the navbar presets.
I hope you can find a solution to this simple problem that will look normal as I have in other platforms that I work with.
The Hamburger menu from the blocks is working fine on the desktop.
Why in yours there is this X problem?
I have found the fix.
It is in the row gap that it should be 6 instead of 4 on the hamburger div.
Doesn’t have to be 35px like you suggested.