Thx Michael

Needing this for my little free prog : https://moiscript.weebly.com/anime-svg.html

For avoid this Manual process :)



Copy it to xyz Tab pressed, or make a ShortCut or Copy inside a text editor and save as Closed_curves.js then put it inside commands folder

Works also with "Multiple" objects!

script:
var objects = moi.geometryDatabase.getSelectedObjects().getBReps();
for ( var i = 0; i < objects.length; ++i )
{
var faces = objects.item(i).getFaces();
for ( var j = 0; j < faces.length; ++j )
{
var loops = faces.item(j).getLoops();
for ( var k = 0; k < loops.length; ++k )
{
var edges = loops.item(k);
var factory = moi.command.createFactory( 'join' );
factory.setInput( 0, edges );
factory.commit();
}
}
}



PS
For kill backfaces in some visible solid volumes (works also with multiple objects )
Separate then
script: moi.geometryDatabase.selectVisible();
Inverse Selection
Erase or Hide