Hierarchy v2: foldout icon disappears after undo parenting

Steps to reproduce:

1. open attached project
2. drag and drop node "E" to node "F" as child
3. undo changes( cmd+Z)

Actual results: The expand/collapse triangle icon disappears 

Expected results: The expand/collapse triangle icon shouldn't disappear 

Reproducible with versions: 6000.5.0a1, 6000.5.0a4

Not reproducible with versions: 6000.4.0a3

Can’t test with versions: 

Tested on (OS): MacOS 26.1

Notes:

• Note that [Internal link] doesn't seem to have fixed the issue and issue still reproduces with latest trunk. See more details in attached video.