Anchor links do not work correctly for headers produced by loops

[archiewood]

Steps To Reproduce

create a page with headers generated by a loop

{#each assessment as assess}

### {assess.name}

Some text

{/each}

Expected Behavior

You can click on the TOC and it will navigate to the correct point in the page

Actual Behaviour

It navigates to the first instance of the loop, as they all have the same href