Cannot move to another page's anchor

🐛 Bug Report

Cannot move to another page’s anchor when clicking the link.

Have you read the Contributing Guidelines on issues?

yes

To Reproduce

1. Add a page named “doc1” with the following contents

## foo
here require large contents enough to scroll
 ...
 ...
 ...
 ...
 ...

## bar
some contents

1. Add a page named “doc2” with the following contents

  [link to another page's anchor](doc1#bar)

1. Build the pages and open the browser
2. Click the link at the page “doc2”

Expected behavior

Move to the “bar” on the page “doc1”

Actual Behavior

Just move to the page “doc1”, but the scroll position is incorrect (=top).

Your Environment

• Docusaurus version used: ^2.0.0-alpha.55
• Environment name and version (e.g. Chrome 83.0.4103.97, Node.js 12.14.0):
• Operating system and version (desktop):

Reproducible Demo

https://shinout.github.io/docusaurus-incorrect-anchor-move-repro/docs

• Click the link doc1#Images at Document Number 2(doc2)

[yangshun]

Oh that’s great! Look @JoelMarcey I hired a fellow without knowing 🎉

[teikjun]

I’ve made a repro for the issue mentioned by @shinout

To Reproduce:

1. Visit https://docusaurus-anchor-repro.now.sh/docs/doc2
2. Click “go to a header written in japanese” link

It goes to the start of the page instead of the actual header

Reproducible Demo: Repo: https://github.com/teikjun/docusaurus-anchor-repro