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minor fixes

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Ilya Kantor 2021-10-25 22:24:10 +03:00
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2-ui/5-loading/02-script-async-defer/article.md
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@ -133,8 +133,12 @@ Async scripts are great when we integrate an independent third-party script into
<script async src="https://google-analytics.com/analytics.js"></script>
```
```smart header="The `async` attribute is only for external scripts"
Just like `defer`, the `async` attribute is ignored if the `<script>` tag has no `src`.
```
## Dynamic scripts
There's one more important way of adding a script to the page.
We can create a script and append it to the document dynamically using JavaScript:
@ -188,7 +192,7 @@ But there are also essential differences between them:
| `async` | *Load-first order*. Their document order doesn't matter -- which loads first runs first | Irrelevant. May load and execute while the document has not yet been fully downloaded. That happens if scripts are small or cached, and the document is long enough. |
| `defer` | *Document order* (as they go in the document). | Execute after the document is loaded and parsed (they wait if needed), right before `DOMContentLoaded`. |
In practice, `defer` is used for scripts that need the whole DOM and/or their relative execution order is important.
In practice, `defer` is used for scripts that need the whole DOM and/or their relative execution order is important.
And `async` is used for independent scripts, like counters or ads. And their relative execution order does not matter.