Array in Array has no 'add' button unless

[ldelaprade]

Prerequisites

• I have searched the existing issues
• I understand that providing a SSCCE example is tremendously useful to the maintainers.
• I have read the documentation
• Ideally, I'm providing a sample JSFiddle, Codesandbox.io or preferably a shared playground link demonstrating the issue.

What theme are you using?

core

Version

5.x

Current Behavior

A very simple schema, multiple 'models', each model can have multiple 'features'.
The top level array triggers an 'add' button, while for inner 'feature' array, you cannot add multiple values
{ "type": "object", "properties": { "models": { "type": "array", "items": { "type": "object", "properties": { "model": { "type": "string" }, "features": { "type": "array", "items": [ { "type": "string" } ] } } } } } }

You can workaround with defining embedded array with 'allOf'

"features": { "type": "array", "items": { "allOf": [ { "type": "string" } ] } }

Expected Behavior

"features": { "type": "array", "items": [ { "type": "string" } ] }

should be trigger same formulat as

"features": { "type": "array", "items": { "allOf": [ { "type": "string" } ] } }

Steps To Reproduce

No response

Environment

- OS:
- Node:
- npm:

Anything else?

No response

[ldelaprade]

actually,
"features": { "type": "array", "items": [ { "type": "string" } ] }
was not a good syntax...
should be
"features": { "type": "array", "items": { "type": "string" } }
and then bug disapears