Browser & Web Performance · Junior · Question 8 of 75

What does a classic `<script src>` without `async` or `defer` do to HTML parsing?

✓Correct answer: Pauses parsing until the script is downloaded and executed
2Runs the script only after the load event
3Nothing, scripts always load in parallel with parsing and run at the end

Explanation

Such a script is parser-blocking, because it might use document.write or read the DOM built so far.

Further reading

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