Console error when picking Block List as property editor

[kjac]

Which Umbraco version are you using? (Please write the exact version, example: 10.1.0)

V14 RC5

Bug summary

When picking Block List as property editor for a new datatype, the JS console reports the following error:

TypeError: Cannot assign to read only property '0' of object '[object Array]'
    at Array.sort (<anonymous>)
    at UmbArrayState.setValue (array-state.js:49:34)
    at UmbDataTypeWorkspaceContext._mergeConfigProperties (data-type-workspace.context.js:145:30)
    at Object.next (data-type-workspace.context.js:108:18)

The datatype configuration seems fully functional despite the JS error.

NOTE: This also applies to Block Grid.

Specifics

No response

Steps to reproduce

1. Create a new datatype and pick the Block List as property editor.
2. Observe the error in the JS console.

Expected result / actual result

No response

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This item has been added to our backlog AB#41888