How do I add Polarr to the Photography section of the Ubuntu App Store?

Polarr is a photography application and should be discoverable under the Graphics and Photography categories of the Ubuntu Software Store. I can find Polarr in Ubuntu Software by directly searching for “polarr”, but Polarr does not show up under the Photography category. I’ve looked through the Snapcraft dashboard (https://dashboard.snapcraft.io/snaps/polarr/update/?step=discovery) for an option to select categories, but I did not see one.

I use electron-builder and have set the category to “Photography” in my package.json file:

  "build": {
    "appId": "co.polarr.photoeditor",
    "linux": {
      "icon": "icon",
      "synopsis": "Powerful and easy-to-use photo editor.",
      "description": "Used by the world's most professional portrait and landscape photographers, Polarr offers advanced auto-enhance tools and sophisticated filters to edit every detail of your photo.",
      "category": "Photography",
      "target": [
        "snap"
      ]
    },
    "appImage": {},
    "snap": {
      "confinement": "strict",
      "summary": "Powerful and easy-to-use photo editor.",
      "grade": "stable",
      "stagePackages": [
        "default",
        "libcanberra-gtk-module",
        "libgail-3-0",
        "libatk1.0-0",
        "unity-gtk-module-common",
        "libvips42",
        "libgl1-mesa-glx"
      ],
      "plugs": [
        "home",
        "x11",
        "unity7",
        "browser-support",
        "network",
        "gsettings",
        "pulseaudio",
        "opengl"
      ]
    }
  },

Categories in the Ubuntu 16.04 Software Store are completely broken and I’ve filed a separate bug report for that: https://bugs.launchpad.net/ubuntu/+source/gnome-software/+bug/1741588

This is what I see in the Ubuntu 17.10 Software Store’s Photography category (missing Polarr):