First of all: I love Quarto, thank you! :partying_face: 

I work on a Quarto website which contains text mostly written in German. There are some headers in articles that contain an _umlaut_ (e.g. __ü__). The TOC does not seem to work properly for those articles, it does not collapse when a graphic is scaled to the page column and it does not update the current location.

On my browser console I get the following error:

```
Uncaught DOMException: Document.querySelector: '#variablen-%C3%BCberpr%C3%BCfen' is not a valid selector
```

I seems to me that my header `# Variablen überprüfen` does not get transformed to a valid CSS selector. I don't know where or how this transformation takes place, but I think there is something wrong.

Tell me if you need more info.
dragonstyle
2022-04-06T15:55:05Z
robfuscator
closed
CSS selectors for TOC items break when markdown header contains an umlaut
https://github.com/quarto-dev/quarto-cli/issues/550