`menu.main` nested items with `pageRef` link to homepage on mobile, but work correctly on desktop

[mragochar]

Description:

I have a menu.main entry with a link-less parent (identifier only) and 3 children using pageRef, structured for a dropdown:

menu:
  main:
    - identifier: devops
      name: Dev Stuffs
      weight: 1
    - name: Git & Github
      pageRef: /git
      parent: devops
      weight: 1
    - name: Docker
      pageRef: /docker
      parent: devops
      weight: 2
    - name: Linux Fundamentals
      pageRef: /linux
      parent: devops

Desktop behavior: All 3 children link correctly to their respective pages.

Mobile behavior (hamburger menu): All 3 children link to the homepage (/) instead of their intended page.

Steps to reproduce:

1. Add a menu.main group as above, with a parent that has no url/pageRef (identifier only), and children using pageRef.
2. Build and view the site on a mobile viewport / narrow browser window.
3. Open the hamburger menu, expand the dropdown, and click any child item.
4. Observe it navigates to the homepage instead of the target page.

Workaround found: Changing the children's pageRef to url (with the equivalent literal path, e.g. pageRef: /git → url: /git/) fixes the mobile links immediately. Desktop behavior is unaffected either way.

Environment:

• Hugo version: hugo v0.163.3-4d22555aebf458d5d150500c9ac4bee5b24cf0d3+extended+withdeploy linux/amd64 BuildDate=2026-06-18T16:18:24Z VendorInfo=gohugoio
• Hextra version: v0.12.3

Question: Why does this happen only on mobile and not desktop? Is this a known bug?