There is a big diversity of how anchor links are rendered which causes bugs and make the css inconsistent, see MDL-54729 MDL-53050

I'm proposing to make a new core renderer so all anchors are consistent, and with an option for the anchor to also render a permalink on hover so that it's easy to discover and deep link to the anchor.

Here is a screen shot of how github renders the permalinks on markdown headings on hover:

Some candidates for refactoring:

1. course format anchors
2. wiki table of contents anchors
3. forum comment linking