Why is JavaScript not multithreaded?

Related questions

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5. Do I need to await an async function?
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7. Is JavaScript sync or async?
8. Is an async method that returns task?
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Tags

1. #concurrency
2. #issues
3. #interpreter
4. #existing
5. #concurrently
6. #would
7. #because
8. #cause
9. #google
10. #browser
11. #chrome
12. #javascript
13. #multi
14. #single
15. #support
16. #pages
17. #afaik
18. #thread
19. #massive
20. #threading