Open Link in new tab

[harryhanYuhao]

Problem

Currently all external https links are opened in the current browser window.
To open an external link in a new tap, one have to use the verbose html tag:
<a href="http://example.com/" target="_blank">Hello, world!</a>.

As mdbook is often used for documentation, it makes sense that links to external reference are opened in a new tab, as our readers still want to refer back to the documentation.

Proposed Solution

Add a custom option to open external links in new tab by default.

Notes

No response