Two NullReferenceException errors are thrown and nodes disappear when renaming a Dropdown from the Graph Inspector in a Sub Graph

How to reproduce:

1. Open the attached “ShaderGraphBug.zip” project
2. Open the "MySubgraph" Sub Graph asset
3. In the Blackboard, select the “MyDropdown”
4. In the Graph Inspector tab, click the Name field
5. Rename the Dropdown
6. Observe the Console and Sub Graph editor view

Actual result: The Console fills with repeating NullReferenceException errors, and the Sub Graph editor view goes blank, all nodes and connections disappear from the graph canvas
Expected result: No errors are logged in the Console, and the Sub Graph editor continues displaying the node graph normally

Reproducible with: 6000.0.0f1, 6000.0.80f1, 6000.3.21f1, 6000.5.6f1, 6000.6.0b6, 6000.7.0a3

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Workarounds:

• Right-click the Dropdown node and select "Disconnect all" before renaming it
• Right-click the MyDropdown node in the Blackboard and select “Rename”

Notes:

• In 6000.0.0f1 and 6000.0.80f1, the bug behaves differently than in later versions, it still produces the same 2 errors, but the graph does not go blank, renaming the Dropdown a second time has no further effect
• First line of both error messages: “NullReferenceException: Object reference not set to an instance of an object”