<base>
What Does It Do?
It is used to set default URL for other tags.
<head>
<base href="https://example.com/" />
</head>
<body>
<a href="path?query=value">link</a>
</body>
target="_blank"
If it is written, the link opens in a new tab.
<head>
<base href="https://example.com/" target="_blank" />
</head>
<body>
<a href="path?query=value">link</a>
</body>
<link> and <script>
These tags are also affected by <base>. So, be careful when you import css or js files.
<head>
<base href="https://example.com/" />
<!-- Local 'style.css' is not going to be applied. -->
<link rel="stylesheet" href="style.css" />
<!-- Local 'script.js' is not going to be applied. -->
<script src="script.js"></script>
</head>