allowing User Role to edit menus, but not other admin-level capabilities

Hi,
I created a new user role based on Editor. The new role should have all the capabilities of Editor – but should also be able to edit menus.

To do so, I choose the checkbox for edit_theme_options and then click update, but the change doesn’t stick and the new user role has no access to edit the menus.

What am I doing wrong?
The site is https://recoveryoptions.us/
Much thanks.

https://www.ads-software.com/plugins/user-role-editor/