Bug: contentEditable attribute does not allow the 'plaintext-only' value

[nathan-osman]

React version: 18.2.0

Steps To Reproduce

1. Create a React project with TypeScript enabled
2. Create an element with the contentEditable="plaintext-only" attribute

Reproducible example:
https://codesandbox.io/s/cool-voice-w8w7q2

The current behavior

The TypeScript compiler flags the attribute as an error:

Type '"plaintext-only"' is not assignable to type 'Booleanish | "inherit"'.ts(2322)

index.d.ts(1988, 9): The expected type comes from property 'contentEditable' which is declared here on type
  'DetailedHTMLProps<HTMLAttributes<HTMLDivElement>, HTMLDivElement>'

The expected behavior

No error is generated. This value is supported for the attribute on several popular browsers, including Chrome, Edge, Safari, and Opera.

[joaquinuriarte]

The file is here: https://github.com/DefinitelyTyped/DefinitelyTyped/edit/master/types/react/index.d.ts.

As of commit [69dbf71], the issue is on line 1955.

A potential solution could be to change:
"contentEditable?: Booleanish | "inherit" | undefined;"
for
"contentEditable?: Booleanish | "inherit" | "plaintext-only" | undefined;"

[joshuadschoep]

I would be able to take this issue (it will be my first contribution to both React and DefinitelyTyped)

[eps1lon]

Fixed in DefinitelyTyped/DefinitelyTyped#67250