No need for mutation observer to load correct theme for giscus

[cderv]

Note

• This is alternative fix for Giscus Javascript not loading iframe correctly #12567 compared to giscus - load immediately if light or dark mode classes present #12569

This reverts

• Update giscus.ejs to fix giscus color on load #11047

I believe work from @gordonwoodhull in

• no flashing when reloading in light or dark mode #12173

has updated logic for handling Light / Dark mode. And this is including loading Giscus theme correctly. So it fixed #8613 too.

Mutation Observer is not needed anymore.

This was tested locally using https://github.com/cderv/quarto-giscus-testing

@gordonwoodhull reading what you've done with Giscus in mind, I believed you handled correct Dark Mode default and pass the theme correctly to giscus. My tests confirms it, but review is welcome in case there is other thing to check for Giscus regarding your dark mode change

[gordonwoodhull]

#12569 should work, but I think this is the better change because it makes the logic simpler instead of more complicated. (By not checking for conditions that will no longer happen.)

I'll write up a more thorough explanation on #12567

[cscheid]

I think this is the better change because it makes the logic simpler instead of more complicated.

Agreed, and I withdrew my PR already :)

[cderv]

Item is already in changelog like this

quarto-cli/news/changelog-1.7.md

Line 181 in 9fa377b

- ([#8613](https://github.com/quarto-dev/quarto-cli/issues/8613)): Fix `giscus` color on load to support dark mode (by @kv9898).

Not sure we need to change it so this is probably good to merge.