**Steps to replicate the issue** (include links if applicable):
* With an extension outputting `<script>` tags with `&` (if-statements) during `ParserAfterTidy` etc.
* Fullfils the condition of one of the `OutputTransform` using `RemexCompatFormatter`, e.g. with a table of contents
* Check the transformed page HTML
----
OR:
* Create a CSS page in the "Sanitized CSS" content model with
```css
a::before {
content: "&";
}
```
* Use it for `<templatestyles>` from a wiki page
* Check the transformed page HTML, or links in the page
**What happens?**:
Ampersands (&) in the `<script>`/`<styles>` tags output by the extension are encoded.
**What should have happened instead?**:
Ampersands (&) in the `<script>`/`<styles>` tags output by the extension stay as-is.
**Software version** (on `Special:Version` page; skip for WMF-hosted wikis like Wikipedia):
Not fixed on the master branch.
**Other information** (browser name/version, screenshots, etc.):
Noticed this because some `OutputTransform`s are backported to 1.43.4