OneBox Preview on Hover

Example...

GitHub
Hover the above link

You can use it on your Ghost site!

Copy this into an HTML Card in the Post Editor (as in the example below, add class="hyperlinks" to any links in your post for which you want the Popup OneBox)...

<a href="https://github.com/" class="hyperlinks">GitHub</a>
    <br />Hover the above link

Put this in your Site (or Post) Header Injection...

<script src="https://cdn.jsdelivr.net/npm/@hyperlinks-js/hyperlinks@2.1.0/dist/index.bundle.js" type="module">
</script>
<script type="module">
Hyperlinks.Init("dark-horizontal"); // You can substitute the theme name with any theme name you want.
</script>

You can find the source and docs on Here...