Highlight in codeblocks- extension of normal hightlight

Feature requests
1

Use case or problem

it would be useful to have highlight in codeblocks

Proposed solution

adding an extension to the event listener detecting the “=”:
when in a codeblock, having a selection, pressing “=” (once should be enough), then the selection is added to the header and the 2 equals removed and so the text highlighted.
there are 2 possibilities. doing an index inside codeblock to get the exact selection, and add for example

```js i0-5 i15-20
codeblock content indexed
```

and modifying the header when there are some overlaps… e.g adding a selection i6-18 previous selections become i0-20
and easier just highlight lines (but really less precise)

Now pressing = again on the same selection will remove the highlight and the header reference.

Current workaround (optional)

Related feature requests (optional)

2

or even better added to the metadata. so the user would have just the same behaviour as normal hightlight. it has to be tested if 1 or 2 = fit better