[graphiql] Tab duplicating when using only shouldPersistHeaders.

[tcK1]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

When refreshing (F5 or cmd/ctrl+r) the page, sometimes the current tab is duplicated without the persisted headers.

Expected Behavior

It should not duplicate the tab.

Steps To Reproduce

Comment all these props besides `shouldPersistHeaders: true,`.

https://github.com/graphql/graphiql/blob/9d9478aea7536d2957e4371cef4f30577db2113d/packages/graphiql/resources/renderExample.js#L99-L110

This is also easily reproduced in the wild using the CDN example and setting the `shouldPersistHeaders: true` prop.

Module pattern

• graphiql-umd
• graphiql-esm
• graphiql-commonjs

Environment

- GraphiQL Version: master
- OS: MacOS
- Browser: chrome

Anything else?

No response

[acao]

closing as duplicate of #2825