Hi, this plugin does not introduce its own capabilities. It uses built-in WordPress manage_options user capability for its menu item:
https://storage.googleapis.com/role-editor/downloads/support/si-contact-form-capability.png
You may find user capability for any admin menu item with a help of “Admin access add-on”:
https://www.role-editor.com/block-admin-menu-items
Just open it for the Administrator role and find needed menu item in the list.
