Context.sublime-menu

[{
  "id": "sublimetransmenu",
  "caption": "Window's Transparency",
  "children": [{
      "id": "sublimetranssubmenu1",
      "caption": "About",
      "checkbox": true,
      "command": "sub_trans_about"
    },
    { "caption": "-" },
    { "id": "sublimetranssubmenunine", "caption": "Level 5", "command": "set_opacity_half", "checkbox": true },
    { "id": "sublimetranssubmenueight", "caption": "Level 4", "command": "set_opacity_six", "checkbox": true },
    { "id": "sublimetranssubmenuseven", "caption": "Level 3", "command": "set_opacity_seven", "checkbox": true },
    { "id": "sublimetranssubmenusix", "caption": "Level 2", "command": "set_opacity_eight", "checkbox": true },
    { "id": "sublimetranssubmenuhalf", "caption": "Level 1", "command": "set_opacity_nine", "checkbox": true },
    { "caption": "-" },
    {
      "id": "sublimetranssubmenu3",
      "caption": "Disable",
      "command": "set_opacity",
      "checkbox": true
    }]
}]