This question has been answered by multiple community members. See the first response.
{
"formtabs":[
{
"MIGX_id":1,
"caption":"Key Images",
"print_before_tabs":"0",
"fields":[
{
"MIGX_id":6,
"field":"image",
"caption":"Image",
"description_is_code":"0",
"inputTVtype":"image",
"sourceFrom":"config",
"sources":[
{
"MIGX_id":1,
"context":"web",
"sourceid":2
}
],
"useDefaultIfEmpty":"0",
"pos":1
},
{ ...ADDITIONAL FORM FIELDS EXCLUDED... }
],
"pos":1
}
],
"contextmenus":"edit_migx||remove_migx",
"extended":{
"migx_add":"Add Image",
"formcaption":"Key Image",
"addNewItemAt":"bottom",
"actionbuttonsperrow":4,
"filtersperrow":4,
"use_custom_prefix":"0",
"gridload_mode":1,
"check_resid":1,
"has_jointable":"yes",
},
"columns":[
{
"MIGX_id":5,
"header":"Image Thumbnail",
"dataIndex":"image",
"sortable":"false",
"show_in_grid":1,
"renderer":"this.renderImage",
"clickaction":"selectFromGrid",
},
{ ...ADDITIONAL COLUMNS EXCLUDED... }
]
}
{
"formtabs":[
{
"MIGX_id":2,
"caption":"Special",
"print_before_tabs":"0",
"fields":[
{ ... SOME FIELDS EXCLUDED ... },
{
"MIGX_id":14,
"field":"special-image",
"caption":"Image",
"description":"Optional graphic specific to this special",
"description_is_code":"0",
"inputTVtype":"migx",
"configs":"keyimages",
"sourceFrom":"config",
"sources":[
{
"MIGX_id":1,
"context":"web",
"sourceid":2
}
],
"useDefaultIfEmpty":"0",
"pos":5
}
],
"pos":1
}
],
"contextmenus":"edit_migx||duplicate_migx||remove_migx",
"extended":{
"migx_add":"Add Special",
"formcaption":"Specials",
"addNewItemAt":"bottom",
"actionbuttonsperrow":4,
"filtersperrow":4,
"use_custom_prefix":"0",
"gridload_mode":1,
"check_resid":1,
"has_jointable":"yes",
},
"columns":[
{ ... COLUMNS EXCLUDED... }
]
}
"sources":[
{
"MIGX_id":1,
"context":"web",
"sourceid":2
},
{
"MIGX_id":2,
"context":"mgr",
"sourceid":2
}
]