Get tab labels of visible relationships in a Form

Here is how to get the hidden tabs (id and label). It can probably be used to remove the elements from the array of all relationships (unless there is no better way)

var tabbar = parent.relationships.relTabbar;

var hidden_tabs = tabbar._hiddentabs;
var len = hidden_tabs.length;

for (i=0;i<len;i++)
{
var hidden_tab_id = hidden_tabs.tabID;
var hidden_tab_title = hidden_tabs.title;
}