markdown preview cannot differentiate same header

[alanwalk]

Hi, I'm the author of Markdown TOC.
I have a issue In my repository, Do you have any idea?
Issue link: alanwalk/markdown-toc#37

[mjbvz]

Repo

1. For the markdown:

<!-- TOC -->

- [Test](#test)
- [Test](#test-1)

<!-- /TOC -->

## Test

## Test

1. Open the markdown preview
2. Click on the second test link in the preview

Expected
Scrolls to second Test header

Actual
Noop