click - set frag1
click - set frag2
click - set frag3 pass 999
click - set frag4
click - set bad frag
click - append frag1
click - remove last add node
click - remove all nodes
Test1:
click - set frag1
click - set frag2
click - set frag3 pass 999
click - set frag4
click - set bad frag
click - append frag1
click - remove last node
click - remove all nodes
Test2: