@mathbunnyru how does this look to you? Maybe @consideRatio is looking at this as well?

you can see a demo here:

https://sphinx-book-theme--669.org.readthedocs.build/en/669/

Thank you for such a quick response @choldgraf!

Now there is some extra text above the anchor.
https://sphinx-book-theme--669.org.readthedocs.build/en/669/notebooks.html#code-blocks-and-image-outputs

Hmmm good point - it is a bit tricky to get just right, because if the top padding is too small then we will accidentally highlight the wrong section and the original problem will come back. I reduced the padding at the top in the latest commit to try to strike a balance. WDYT?

I think it looks better now, but I still see the text from the previous part. I guess it's impossible to have both things.

OK how's this? It means that if we have two headers directly after one another, we might accidentally highlight the second, but maybe that's not such a big deal and also not common.

Now it looks great to me 👍

OK I cleaned up a few other points that @mathbunnyru noted - will merge this if tests are happy since it's fixing a few bugs