Table Of Contents doesn't appear when loading a survey JSON after a survey was rendered

[JaneSjs]

T22736 - Issues found in survey js latest version
https://surveyjs.answerdesk.io/internal/ticket/details/T22736

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To reproduce the issue, run the demo from a user's ticket. You see that a survey is initially loaded empty. Type something into an input box. A survey JSON (json.js) is loaded using the survey.fromJSON function when a survey component is rendered. At this point, a TOC doesn't appear even though it's enabled in a survey JSON definition.