Remove 'prerender' value from VisibilityState

[kripod]

Search Terms

prerender, visibility

Suggestion

According to MDN, the value 'prerender' has been deprecated and cannot be found in the current version of the official Page Visibility API specification.

As mentioned in the document's introduction, "Without knowing the visibility state of a page, web developers have been designing web pages as if they are always visible". I would propose adhering to the standard and using the 'visible' value by default.

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

[MartinJohns]

[x] This wouldn't be a breaking change in existing TypeScript/JavaScript code

Technically this is a breaking change for everyone who makes use of that value already.

Related: #390