Answered Saving data on joined alias

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  "contextmenus":"",
  "actionbuttons":"",
  "columnbuttons":"",
  "filters":"",
  "extended":{
    "migx_add":"",
    "disable_add_item":"",
    "add_items_directly":1,
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    "getlistsortdir":"",
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    "gridpagesize":50,
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    "getlistwhere":{
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        "alias":"Profile"
      },
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        "alias":"UserGroup",
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      "MIGX_id":1,
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      "customrenderer":"",
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      "editor":"this.textEditor"
    },
    {
      "MIGX_id":3,
      "header":"Username",
      "dataIndex":"username",
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    {
      "MIGX_id":4,
      "header":"Email",
      "dataIndex":"Profile_email",
      "width":"",
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      "show_in_grid":1,
      "customrenderer":"",
      "renderer":"",
      "clickaction":"",
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      "editor":""
    },
    {
      "MIGX_id":6,
      "header":"Blocked",
      "dataIndex":"Profile_blocked",
      "width":40,
      "sortable":true,
      "show_in_grid":1,
      "customrenderer":"",
      "renderer":"this.renderSwitchStatusOptions",
      "clickaction":"switchOption",
      "selectorconfig":"",
      "renderchunktpl":"",
      "renderoptions":[
        {
          "MIGX_id":1,
          "name":"blocked",
          "use_as_fallback":"",
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          "image":"assets\/components\/migx\/style\/images\/cross.png"
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          "image":"assets\/components\/migx\/style\/images\/cb_empty.png"
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      "editor":""
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}