Window `visible: false` doesn't work on KDE/GNOME X11/Wayland

[ruby falcon]

Using ArchLinux x64 on Gnome 43.2

My windows object:

    "windows": [
      {
        "label": "main",
        "fullscreen": false,
        "height": 900,
        "width": 1600,
        "minWidth": 1360,
        "minHeight": 720,
        "resizable": true,
        "title": "Λ ＮＩＭ Λ",
        "visible": false
      },
      {
        "width": 1200,
        "height": 650,
        "maxWidth": 1200,
        "maxHeight": 650,
        "minWidth": 920,
        "minHeight": 500,
        "decorations": false,
        "url": "/splashscreen",
        "transparent": true,
        "resizable": true,
        "center": true,
        "label": "splashscreen"
      }
    ]

Expected the app to open with the main window hidden
It's not what happens.

[ruby falcon]

Update: it's also not making ANYTHING invisible on KDE Plasma 5.26 either

tested both DE's with Wayland and X11
Same result