When starting multiple overlays, only the first one has persistent storage

[Epithumia]

If I start only one overlay, it will behave as expected, I can modify its settings, and they are persisted through restarts. However, if I start a second overlay while the first one is running, whether it's with web-overlay start <id> or because I used web-overlay start (with no overlay running), that second overlay will not persist its settings, either because they are not saved, or because the setting are not reread when it's not the first overlay started.

For example with the following settings:

{
  "overlays": [
    {
      "id": "Kagerou",
      "name": "Kagerou",
      "url": "http://proxy.iinact.com/overlay/kagerou/?HOST_PORT=ws://127.0.0.1:10501",
      "wsUri": "",
      "position": { "x": 50, "y": 100 },
      "size": { "width": 500, "height": 250 },
      "opacity": 0.9,
      "clickThrough": true,
      "alwaysOnTop": true
    },
    {
      "id": "MopiMopi",
      "name": "MopiMopi",
      "url": "http://proxy.iinact.com/overlay/mopimopi/?HOST_PORT=ws://127.0.0.1:10501",
      "wsUri": "",
      "position": { "x": 50, "y": 100 },
      "size": { "width": 600, "height": 400 },
      "opacity": 0.9,
      "clickThrough": true,
      "alwaysOnTop": true
    },
    {
      "id": "Cactbot",
      "name": "Cactbot",
      "url": "http://proxy.iinact.com/overlay/cactbot/ui/raidboss/raidboss.html?OVERLAY_WS=ws://127.0.0.1:10501/ws",
      "wsUri": "",
      "position": { "x": 100, "y": 100 },
      "size": { "width": 600, "height": 400 },
      "opacity": 0.9,
      "clickThrough": true,
      "alwaysOnTop": true
    }
  ],
  "globalSettings": {
    "startWithSystem": false,
    "defaultOpacity": 0.9,
    "defaultClickThrough": true
  }
}

Only Kagerou will have persistent settings, and MopiMopi/Cactbot will revert to their default settings.