Site title link in side bar is broken when first loading or refresh

[onevcat]

The site title below search box in side bar is broken.

Reproduce

Case 1

1. Open any page directly, like https://docsify.js.org/#/quickstart
2. The "docsify" title (which should navigate us to the main page) in side bar can not be clicked.

Workaround: load another page by clicking a link in side bar. Now the title link could be clicked.

Case 2

Follow the workaround in case 1, and refresh the page. Title link cannot be clicked again.